@article { ISI:000273349000001, title = {Bond length variations: electron number profiles and transferable atomic sizes}, journal = {Journal of Molecular Structure}, volume = {936}, number = {1-3}, year = {2009}, month = {NOV}, pages = {1-8}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A profile of the number of electrons with distance along the M-X bond in gas-phase diatomic molecules has been obtained from electron density plots calculated using DFT B3LYP 6-311G** method for some representative molecules. This {\textquoteleft}{\textquoteleft}number profile{\textquoteright}{\textquoteright} is compared with that expected from the partitioning of the 1D bond-distance into atom-specific transferable {\textquoteleft}{\textquoteleft}hub{\textquoteright}{\textquoteright} or core atomic sizes of the M and X atoms and another {\textquoteleft}{\textquoteleft}axle{\textquoteright}{\textquoteright} size which is associated with a pair of (bonding) electrons. The {\textquoteleft}{\textquoteleft}hub{\textquoteright}{\textquoteright} size is proportional to a core atom-specific size, r(nZ)(c) with r(nZ)(c)(M) \>= r(nZ)(c)(X). For {\textquoteleft}{\textquoteleft}single bonds{\textquoteright}{\textquoteright}, the {\textquoteleft}{\textquoteleft}hub{\textquoteright}{\textquoteright} size for M atom is C(M)r(nZ)(c)(M) and for X atom is C(X)r(nZ)(c)(X). The {\textquoteleft}{\textquoteleft}axle{\textquoteright}{\textquoteright} size, DMX, is usually the ordinary (similar to 4a(H)/3 where a(H) is the Bohr radius of the hydrogen atom) or elongated (similar to 2a(H)) bond length of the hydrogen molecule. The {\textquoteleft}{\textquoteleft}hub{\textquoteright}{\textquoteright} and {\textquoteleft}{\textquoteleft}axle{\textquoteright}{\textquoteright} sizes could be characterized {\textquoteleft}{\textquoteleft}charge-transfer{\textquoteright}{\textquoteright} (C(M) = pi(2/3) = 2.144; C(X) = pi(4/3)/2 = 2.300 and D(MX) = 4a(H)/3) or {\textquoteleft}{\textquoteleft}neutral{\textquoteright}{\textquoteright} (CM or C(X) = 1, 2, ... and D(MX) = 2a(H)). We use a new {\textquoteleft}{\textquoteleft}static{\textquoteright}{\textquoteright} or {\textquoteleft}{\textquoteleft}peripatetic{\textquoteright}{\textquoteright} classification for the core sizes which is derived from a new condition for metallization in elements based on atomic size. The charge-transfer distance, d(MX)(+/-), is usually found for {\textquoteleft}{\textquoteleft}static{\textquoteright}{\textquoteright} conditions while the {\textquoteleft}{\textquoteleft}neutral{\textquoteright}{\textquoteright} description is usually found when X = F or for {\textquoteleft}{\textquoteleft}peripatetic{\textquoteright}{\textquoteright} conditions. Such a partitioning is seen to agree with that from the plot of the total number of electrons, N(el), vs r along a bond axis. The Nel vs r plots from each atom are described by a simple hydrogen-atom-like function which differ away ({\textquoteright}{\textquoteright}out{\textquoteright}{\textquoteright}) or towards ({\textquoteright}{\textquoteright}in{\textquoteright}{\textquoteright}) the M-X bond. Thus N(in,out)(M, X) = (Z(M,X) +/- 1) exp (-r/B(in,out)) where the minus sign is associated with M and plus sign with X and Bin, out being related inversely to the Slater orbital exponent. (C) 2009 Elsevier B.V. All rights reserved.

}, keywords = {B3LYP, Bond length, Bond-stretch isomer, DFT, Diatomic molecule}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2009.07.007}, author = {Ganguly, Parthasarathy and Kulkarni, Bhakti S. and Pal, Sourav} } @article { ISI:000278112200007, title = {Effect of solvents having different dielectric constants on reactivity: a conceptual DFT approach}, journal = {International Journal of Quantum Chemistry}, volume = {110}, number = {9}, year = {2010}, month = {AUG}, pages = {1642-1647}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Conceptual density functional theory is exploited to understand the reactivity in a medium of solvents with increasing dielectric constants. Aprotic as well as protic solvents are used for this study. It is found that the global parameters, such as chemical potential and hardness, decrease from gas phase to solvent phase with increasing dielectric constant. However, it is observed that the Fukui functions of the reactive atoms increase significantly with the dielectric constants of the aprotic solvents while for the protic solvents the variation of the reactivity indices is insignificant. (C) 2009 Wiley Periodicals, Inc. Int J Quantum Chem 110: 1642-1647, 2010

}, keywords = {COSMO, DFT, dielectric constant, Reactivity descriptors, solvent effect}, issn = {0020-7608}, doi = {10.1002/qua.22333}, author = {Kar, Rahul and Pal, Sourav} } @article { ISI:000294340300007, title = {Understanding the molecular conformations of Na-dimyristoylphosphatidylglycerol (DMPG) using DFT-based method}, journal = {Molecular Simulation}, volume = {37}, number = {11}, year = {2011}, month = {AUG}, pages = {953-963}, publisher = {TAYLOR \& FRANCIS LTD}, address = {4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND}, abstract = {

The molecular conformations of phospholipids comprising a lipid bilayer determine the physico-chemical properties of the latter. In this study, we attempt to understand the various possible conformations available for an anionic lipid molecule dimyristoylphosphatidylglycerol (DMPG) with Na as its charge-compensating cation. The various possible molecular orientations available for lipid molecule are analysed using a density functional theory-based method. Our study reveals a rich conformational space with two different types of glycerol body orientations, more commonly known as rotamers. Interestingly, this is in agreement with the molecular conformations proposed earlier by NMR studies on lipid monomer solutions. We demonstrate that these conformations are an outcome of delicate balance of electrostatic and van der Waals forces along with intra-molecular hydrogen bonds achieved by a critical combination of torsion angles. Na(+) ions are seen to interact predominantly with the oxygen atoms of the glycerol groups in tail and head along with that of phosphate oxygen atoms leading to a cage-like orientation of lipid molecule around the Na(+). Following the conformational analysis, we attempt to evaluate the electronic properties of few low-lying conformations. This study shows that though the water molecules screen the Na-O(lipid) interactions, they do not dramatically modify the Na-O(lipid) bond distances. The lipid conformation retains the cage-like structure around the Na(+) in the presence of water molecules. Some amount of charge transfer from the water molecules to Na ion is noted. The water molecules modify the phosphate-tail glycerol group interactions leading to a more stable Na-DMPG-H(2)O and Na-DMPG-4H(2)O complexes.

}, keywords = {DFT, DMPG, molecular conformations, rotamer and hydration energy}, issn = {0892-7022}, doi = {10.1080/08927022.2011.582105}, author = {Mishra, Deepti and Pal, Sourav and Krishnamurty, Sailaja} } @article { ISI:000302296000032, title = {Behaviour of density functional theory for electric response properties at distorted geometries of molecules}, journal = {Theoretical Chemistry Accounts}, volume = {131}, number = {2}, year = {2012}, month = {FEB}, pages = {1094}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

The role of exchange-correlation is well known for accurate calculations of electric response properties. The exchange-correlation functional in density functional theory (DFT) has been well studied for ground state equilibrium geometry. However, the behaviour of these functional in stretched geometries, where static correlation play an important role, has not been studied systematically, particularly for response electric properties. Thus, we present here the rigorous calculation of electric response properties at distorted geometries of the molecules. We have considered dipole polarizability and dipole-quadrupole polarizability for description of role of static and dynamic correlation for electric response properties. The calculations are performed with our new approach, noniterative approximation to coupled-perturbed Kohn-Sham method. These DFT results are compared with higher level ab initio such as coupled perturbed singles and doubles and fully correlated full CI. We have studied single, double and triple-bonded systems at different inter-nuclear separation. We report here the dipole polarizability and dipole-quadrupole polarizability of HF, BH, H2CO, CO and NO+. We also present the effect of basis and functional on polarizability and dipole-quadrupole polarizability.

}, keywords = {DFT, Dipole-dipole polarizability, Dipole-quadrupole polarizability, Distorted geometry, NIA-CPKS}, issn = {1432-881X}, doi = {10.1007/s00214-012-1094-1}, author = {Shedge, Sapana V. and Joshi, Sayali P. and Pal, Sourav} } @article { ISI:000301128300003, title = {Radical mediated deoxygenation of inositol benzylidene acetals: conformational analysis, DFT calculations, and mechanism}, journal = {Carbohydrate Research}, volume = {351}, year = {2012}, month = {APR}, pages = {26-34}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

Xanthates of 1,3-benzylidene acetal derivatives of myo- and neo-inositols undergo dideoxygenation under Barton-McCombie conditions, as a result of intramolecular abstraction of the benzylidene acetal hydrogen and subsequent cleavage of the acetal ring. Scrutiny of structure of these bicyclic inositol derivatives shows that although the conformation of the two rings can vary depending on the configuration of the inositol ring and the phase in which the molecules are present, both the xanthates lead to the formation of the same dideoxyinositol. DFT calculations on these molecular systems suggest that neo-inositol derivatives undergo conformational change prior to radical formation while myo- inositol derivatives undergo conformational change subsequent to radical formation, during the deoxygenation reaction. A low barrier for intramolecular hydrogen transfer supports the extreme facility of this deoxygenation reaction. (C) 2012 Elsevier Ltd. All rights reserved.

}, keywords = {Deoxygenation, DFT, Inositol, Mechanism, Radical, Xanthate}, issn = {0008-6215}, doi = {10.1016/j.carres.2012.01.001}, author = {Gurale, Bharat P. and Vanka, Kumar and Shashidhar, Mysore S.} } @article { ISI:000326674800001, title = {GIAO/DFT studies on 1,2,4-triazole-5-thiones and their propargyl derivatives}, journal = {Magnetic Resonance in Chemistry}, volume = {51}, number = {12}, year = {2013}, month = {DEC}, pages = {767-774}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Density functional theory (DFT)/Becke-Lee-Yang-Parr (B3LYP) and gauge-including atomic orbital (GIAO) calculations were performed on a number of 1,2,4-triazole derivatives, and the optimized structural parameters were employed to ascertain the nature of their predominant tautomers. C-13 and N-15 NMR chemical shifts of 3-substituted 1,2,4-triazole-5-thiones and their propargylated derivatives were calculated via GIAO/DFT approach at the B3LYP level of theory with geometry optimization using a 6-311++G** basis set. A good agreement between theoretical and experimental C-13 and N-15 NMR chemical shifts could be found for the systems investigated. The data generated were useful in predicting N-15 chemical shifts of all the nitrogen atoms of the triazole ring, some of which could not be obtained in solution state N-15 HMBC/HSQC NMR measurements. The energy profile computed for the dipropargylated derivatives was found to follow the product distribution profile of regioisomers formed during propargylation of 1,2,4-triazole thiones. Copyright (c) 2013 John Wiley \& Sons, Ltd.

}, keywords = {1, 2, 4-triazole-5-thiones, C-13, DFT, GIAO, N-15, NMR, Regioisomers, tautomers}, issn = {0749-1581}, doi = {10.1002/mrc.4012}, author = {Phalgune, Usha D. and Vanka, Kumar and Rajamohanan, P. R.} } @article { ISI:000326296800033, title = {Role of substituents on the reactivity and electron density profile of diimine ligands: a density functional theory based study}, journal = {Journal of Chemical Sciences}, volume = {125}, number = {5}, year = {2013}, month = {SEP}, pages = {1247-1258}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

In this paper, we study the reactivity of diimines like 2, 2({\textquoteright})-bipyridine, 1, l0-phenanthroline and 1, 2, 4-triazines using density-based reactivity descriptors. We discuss the enhancement or diminution in the reactivity of these ligands as a function of two substituent groups, namely methyl (-CH3) group and phenyl (-C6H5) group. The global reactivity descriptors explain the global affinity and philicity of these ligands, whereas the local softness depicts the particular site selectivity. The inter-molecular reactivity trends for the same systems are analysed through the philicity and group philicity indices. The sigma-donor character of these ligands is quantified with the help of electron density profile. In addition, the possible strength of interaction of these ligands with metal ions is supported with actual reaction energies of Ru-L complexes.

}, keywords = {2, 2 {\textquoteleft}-bipyridine, DFT, diimine, Reactivity descriptors, Ru-ligand interaction, substituent effects}, issn = {0974-3626}, doi = {10.1007/s12039-013-0469-8}, author = {Kulkarni, Bhakti S. and Mishra, Deepti and Pal, Sourav} } @article { ISI:000351969900008, title = {First naphthosemiquinone complex of K+ with vitamin K3 analog: experiment and density functional theory}, journal = {Journal of Molecular Structure}, volume = {1088}, year = {2015}, month = {MAY}, pages = {56-63}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Synthesis and characterization of potassium complex of 2-hydroxy-3-methyl-1,4-naphthoquinone (phthiocol), the vitamin K3 analog, has been carried out using FT-IR, UV-Vis, H-1 and C-13 NMR, EPR, cyclic voltammetry and single crystal X-ray diffraction experiments combined with the density functional theory. It has been observed that naphthosemiquinone binds to two K+ ions extending the polymeric chain through bridging oxygens O(2) and O(3). The crystal network possesses hydrogen bonding interactions from coordinated water molecules showing water channels along the c-axis. C-13 NMR spectra revealed that the complexation of phthiocol with potassium ion engenders deshielding of C(2) signals, which appear at delta = similar to 14.6 ppm whereas those of C(3) exhibit up-field signals near delta similar to 6.9 ppm. These inferences are supported by the M06-2x based density functional theory. Electrochemical experiments further suggest that reduction of naphthosemiquinone results in only a cathodic peak from catechol. A triplet state arising from interactions between neighboring phthiocol anion lead to a half field signal at g = 4.1 in the polycrystalline X-band EPR spectra at 133 K. (C) 2015 Elsevier B.V. All rights reserved.

}, keywords = {C-13 NMR, DFT, hydrogen bonding, Naphthosemiquinone, Phthiocol, Vitamin K3}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2015.01.053}, author = {Kathawate, Laxmi and Gejji, Shridhar P. and Yeole, Sachin D. and Verma, Prakash L. and Puranik, Vedavati G. and Salunke-Gawali, Sunita} } @article { ISI:000377374500003, title = {Does the position of the electron-donating nitrogen atom in the ring system influence the efficiency of a dye-sensitized solar cell? A computational study}, journal = {Journal of Molecular Modeling}, volume = {22}, number = {6}, year = {2016}, month = {JUN}, pages = {121}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

We have reported a number of new metal-free organic dyes (2-6) that have cyclic asymmetric benzotripyrrole derivatives as donor groups with peripheral nitrogen atoms in the ring, fluorine and thiophene groups as pi-spacers, and a cyanoacrylic acid acceptor group. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were employed to examine the influence of the position of the donor nitrogen atom and pi-conjugation on solar cell performance. The calculated electron-injection driving force (Delta G(inject)), electron-regeneration driving force (Delta G(regen)), light-harvesting efficiency (LHE), dipole moment (mu(normal)), and number of electrons transferred (Delta q) indicate that dyes 3, 4, and 6 have significantly higher efficiencies than reference dye 1, which exhibits high efficiency. We also extended our comparison to some other reported dyes, 7-9, which have a donor nitrogen atom in the middle of the ring system. The computed results suggest that dye 6 possesses a higher incident photon to current conversion efficiency (IPCE) than reported dyes 7-9. Thus, the use of donor groups with peripheral nitrogen atoms appears to lead to more efficient dyes than those in which the nitrogen atom is present in the middle of the donor ring system.

}, keywords = {DFT, Dye-sensitized solar cells, Organic dyes, Position effect, TD-DFT}, issn = {1610-2940}, doi = {10.1007/s00894-016-2976-2}, author = {Biswas, Abul Kalam and Barik, Sunirmal and Das, Amitava and Ganguly, Bishwajit} } @article { ISI:000380038000012, title = {Site-selective synthesis and characterization of BODIPY-acetylene copolymers and their transistor properties}, journal = {Journal of Polymer Science Part A-Polymer Chemistry}, volume = {54}, number = {13}, year = {2016}, month = {JUL}, pages = {1978-1986}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

To study the effect of site-selective copolymerization of borondipyrromethene (BODIPY) with acetylene on the structural and optoelectronic properties, three copolymers P1-P3 were synthesized by the Sonogashira cross-coupling of BODIPY units with diacetylene and bromine capping through all the possible linkages: alpha-alpha (P1), alpha-beta (P2), and beta-beta (P3). The optoelectronic properties of the polymers were investigated systematically to understand the effect of site-selective polymerization. The HOMO levels of the polymers were significantly tuned from P1 to P3 with negligible change in the LUMO levels. Broadening of absorption spectra from P3 to P1 was observed because of increase in the extent of conjugation. Additionally, the charge transport properties of these polymers in organic thin-film transistors (OTFTs) revealed that P1 and P3 exhibited only p-type mobility, whereas P2 exhibited electron mobility. Notably, the further investigations of the surface morphology of polymer films by atomic force microscopy (AFM) unveiled that comb like nanostructural arrangements in P3 was beneficial for the charge-carrier mobility over the circular arrangements in P1 and P2. (C) 2016 Wiley Periodicals, Inc.

}, keywords = {acetylene, BODIPY, DFT, low-band gap}, issn = {0887-624X}, doi = {10.1002/pola.28064}, author = {Debnath, Sashi and Singh, Saumya and Bedi, Anjan and Krishnamoorthy, Kothandam and Zade, Sanjio S.} } @article {43904, title = {Binding selectivity of vitamin K3 based chemosensors towards nickel(II) and copper(II) metal ions}, journal = {Journal of molecular Structure}, volume = {1143}, year = {2017}, month = {SEP}, chapter = {495-514}, abstract = {

The vitamin K3 derivatives 2-methyl-3-[(pyridin-2-ylmethyl)-amino]-1,4-naphthoquinone (M-1), 2-methyl-3-[(pyridin-2-ylethyl)-amino]-1,4-naphthoquinone (M-2), 2-methyl-3-((2-(thiophen-2-yl) methyl)amino)naphthalene-1,4-dione (M-3) and 2-methyl-3-((2-(thiophen-2-yl)ethyl)amino)naphthalene-1,4-dione (M-4) have been synthesized, characterized and studied for their chemosensor abilities towards transition metal ions. Crystal structures of M-1 to M-4 revealed a variety of N-H center dot center dot O, C-H center dot center dot center dot O, C-H center dot center dot center dot pi and pi center dot center dot center dot pi interactions. Minor variations in such interactions by chemical stimuli such as metal ions, results in change in color that can be visualized by naked eyes. It has been shown that electronic structure and H-1 NMR, vibrational as well as electronic spectra from the density functional theory agree well with the experiments. The metal ion binding in ethanol, ethanol-water and in mild base triethylamine brings forth recognizing ability of M-1 toward Ni2+ whereas M-2 exhibits large sensing ability for Cu2+ ion. Interestingly M-1 display varying metal ion binding specificity in different solvents with the association constant in ethanol being 11,786 M-1 for Ni2+ compared to 9462 M-1 for the Cu2+. A reversal in preferential binding of M-2 with the respective association constants being 4190 M-1 and 6370 M-1 is discernible. (C) 2017 Elsevier B.V. All rights reserved.

}, keywords = {Aminonaphthoquinone Molecular-structures, Anthraquinone, Aqueous-solution, Chemosensor, Crystal-structures, Cu(II), Derivatives, DFT, Fluorometric Chemosensors, hydrogen bonding, Naphthoquinone, pi-pi stacking, Recognition, sensors}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2017.04.094}, author = {Patil, Amit and Lande, Dipali N. and Nalkar, Archana and (Gejji, Shridhar P. and Chakrovorty, Debamitra and Gonnade, Rajesh and Moniz, Tania and Rangel, Maria and Pereira, Eulalia and Salunke-Gawali, Sunita} } @article {43963, title = {Novel interaction study of Th(IV) and Zr(IV) with 4-sulfonatocalix[6]arene: experimental and theoretical investigation}, journal = {Polyhedron}, volume = {137}, year = {2017}, month = {NOV}, pages = {137}, type = {Journal Article}, abstract = {

Calixarenes based ligands are well known in the extraction of heavy metal ions. The modifications at lower as well as upper rim increase the new possibilities of metal extraction in terms of quantum and selectivity of metal. In comparison to calix[4]arene, complexing nature of calix[6]arene is less studied due to its large size and flexible nature. In the present study, 4-sulfonatocalix[6]arene (SCX6) is synthesized and an attempt has been made to understand its complexation behavior with Th(IV) and Zr(IV) metal ions. The effect of different solvents has been examined along with calculation of binding constants for better complexation possibilities. Though in general, its complexation proves to be at 1:1 stoichiometry with respect to ligand and metal, the specific metals show its characteristic modes of interaction with the ligand. This has been understood through IR spectroscopic analysis and density functional theory based first principle studies. 1H NMR spectra of SCX6 and its complexes with Th(IV) and Zr(IV) metal ions was established. IR, UV{\textendash}Vis, fluorescence spectroscopic studies provided a systematic understanding about the binding behavior of these two metals including interference possibilities from other metals.

}, keywords = {4-Sulfonatocalix[6]arene, DFT, metal complexation, Th(IV) Zr(IV)}, doi = { 10.1016/j.poly.2017.08.026}, author = {Rathod, N.V.}, editor = {Joshi, K.} } @article {44165, title = {Tetranuclear cubane Cu4O4 complexes as prospective anticancer agents: Design, synthesis, structural elucidation, magnetism, computational and cytotoxicity studies}, journal = {Inorganic Chimica Acta}, volume = {473}, year = {2018}, month = {MAR}, pages = {121-132}, abstract = {Two new homometallic Cu4O4 cubane clusters 1 and 2 have been synthesized by self-assembly of copper (II) acetate and ligand, 2-[(2-Hydroxy-3-methoxy-benzylidene)-amino]-2-hydroxymethyl-propane-1, 3-diol (H4L) and characterized thoroughly by various spectroscopic techniques and single crystal X-ray diffraction analysis. Temperature- dependent magnetic susceptibility measurements have been performed to elucidate the antiferromagnetic and ferromagnetic nature in Cu4O4 clusters 1 and 2, respectively. In vitro DNA binding studies of cubane clusters were carried out by employing optical spectroscopic techniques. Gel electrophoretic mobility assay performed to examine the nuclease activity of the complexes 1 and 2 with pBR322 DNA, and results revealed oxidative DNA cleavage via reactive oxygen species (ROS) species viz., O-2(.-), O-1(2), etc. In vitro cell proliferation via MTT assay was studied to calculate the cytotoxicity of complexes 1 and 2. The IC50 evaluated were similar to 20 mu M in MCF-7 (Breast) and similar to 30-35 mu M in HepG2 (Liver) cancer cell lines. Additionally, in the presence of 1 and 2, ROS and TBARS (Thiobarbituric acid reactive substance) levels amplified significantly, coupled with GSH (glutathione) levels in cancer lines. Hence, the results exhibited the major role of ROS in apoptosis induced by 1 and 2 clusters and validate their prospective to be efficient anticancer drug entities. (C) 2018 Elsevier B.V. All rights reserved.}, keywords = {Cu4O4 cubane complexes, Cytotoxicity, DFT, DNA binding, Magnetism, Nuclease activity}, issn = {0020-1693}, doi = {10.1016/j.ica.2017.12.039}, author = {Usman, Mohammad and Arjmand, Farukh and Khan, Rais Ahmad and Alsalme, Ali and Ahmad, Musheer and Sen Bishwas, Mousumi and Tabassum, Sartaj} } @article {45538, title = {Aluminum cluster for CO and O-2 adsorption}, journal = {Journal of Molecular Modeling}, volume = {25}, year = {2019}, month = {JAN}, pages = {2}, type = {Article}, abstract = {

Low temperature oxidation of CO to CO2 is an important process for the environment. Similarly adsorption of CO from the releasing sources is also of major concern today. Whereas the potential of gold and silver clusters is well proven for thecatalysis of the above mentioned reaction, the potential of aluminum (Al) clusters remains unexplored. The present study proves that, similar to the transition metals, Al clusters can also be used for adsorption of gases. We first tested the potential of Al cluster as adsorbents for CO. The high binding energy (BE) values prove that Al clusters can be used for adsorbing both CO and O-2. Since oxygen binding is more facile, we adsorbed oxygen on Al and then checked the effect of this O-2 on the BE of CO. The results were obtained by DFT calculations at M062X/TZVP level of theory.

}, keywords = {Aluminum clusters, Charge decomposition analysis, CO adsorption, DFT, O-2 adsorption, Wiberg bond indices}, issn = {1610-2940}, doi = {10.1007/s00894-018-3869-3}, author = {Samanta, Bipasa and Sengupta, Turbasu and Pal, Sourav} } @article {45535, title = {Nature of electrophilic oxygen: insights from periodic density functional theory investigations}, journal = {Surface Science}, volume = {679}, year = {2019}, month = {JAN}, pages = {188-195}, type = {Article}, abstract = {

Increasing demand of ethylene oxide and the cost of versatile chemical ethene has been a driving force for understanding mechanism of epoxidation to develop highly selective catalytic process. Direct epoxidation is a proposed mechanism which in theory provides 100\% selectivity. A key aspect of this mechanism is an electrophilic oxygen (O-ele) species forming on the Ag surface. In the past two and half decades, large number of theoretical and experimental investigations have tried to elucidate formation of O-ele, on Ag surface with little success. Equipped with this rich literature on Ag-O interactions, we investigate the same using periodic DFT calculations to further understand how silver surface and oxygen interact with each other from a chemical standpoint. Based on energetics, Lowdin charges, topologies and pdos data described in this study, we scrutinize the established notions of O-ele. Our study provides no evidence in support of O-ele, being an atomic species nor a diatomic molecular species. In fact, a triatomic molecular species described in this work bears multiple signatures which are very convincing evidence for considering it as the most sought for electrophilic entity.

}, keywords = {Ag(100), DFT, Electrophilic, epoxidation, Nucleophilic oxygen}, issn = {0039-6028}, doi = {10.1016/j.susc.2018.09.009}, author = {Kenge, Nivedita and Pitale, Sameer and Joshi, Kavita} } @article {45480, title = {Synthesis, characterization, pharmacological and computational studies of 4, 5, 6, 7-tetrahydro-1, 3-benzothiazole incorporated azo dyes}, journal = {Journal of Molecular Structure}, volume = {1179}, year = {2019}, month = {MAR}, pages = {630-641}, type = {Article}, abstract = {

The present work describes the synthesis of five novel heterocyclic azo dyes (4a-4e) through conventional diazo-coupling reaction of 4, 5, 6, 7-tetrahydro-1, 3-benzothiazole with various coupling compounds at 0-5 degrees C. The chemical structures of the synthesized azo dyes were characterized by both theoretical and experimental techniques. All the synthesized molecules were evaluated for their antioxidant activity by two different techniques such as DPPH and FRAP. The results indicated that all the synthesized compounds proved to be potent antioxidants. The anti-mycobacterial activity of the azo dyes was tested against M. tuberculosis and the compounds 4a and 4e showed higher activity among the tested dyes. The DNA binding studies showed effective intercalation properties between the azo dyes and CT-DNA. Finally, the molecular docking studies indicated a possible interaction of the azo dyes with target receptor RpsA. (C) 2018 Elsevier B.V. All rights reserved.

}, keywords = {Azo dyes, Benzothiazole, CT-DNA, DFT, tuberculosis}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2018.11.041}, author = {Maliyappa, M. R. and Keshavayya, J. and Mallikarjuna, N. M. and Krishna, P. Murali and Shivakumara, N. and Sandeep, Telkar and Sailaja, Krishnamurty and Nazrulla, Mohammed Azeezulla} } @article {46716, title = {Amidinato germylene-zinc complexes: synthesis, bonding, and reactivity}, journal = {Chemistry-An Asian Journal}, volume = {15}, year = {2020}, month = {OCT }, pages = {3116-3121}, type = {Article}, abstract = {

Despite the explosive growth of germylene compounds as ligands in transition metal complexes, there is a modicum of precedence for the germylene zinc complexes. In this work, the synthesis and characterization of new germylene zinc complexes [PhC(NtBu)(2)Ge{N(SiMe3)(2)}-\> ZnX2](2)(X= Br (2) and I (3)) supported by (benz)-amidinato germylene ligands are reported. The solid-state structures of2and3have been validated by single-crystal X-ray diffraction studies, which revealed the dimeric nature of the complexes, with distorted tetrahedral geometries around the Ge and Zn center. DFT calculations reveal that the Ge-Zn bonds in2and3are dative in nature. The reaction of2with elemental sulfur resulted in the first structurally characterized germathione stabilized ZnBr(2)complexes PhC(NtBu)(2)Ge(=S){N(SiMe3)(2)}-\> ZnBr2(5). Therefore, the Ge=S in5is in-between Ge-S single and Ge=S double bond length, owing to the coordination of a sulfur lone pair of electrons to ZnBr2.

}, keywords = {DFT, Germathione, Germylene, X-ray Structure, zinc}, issn = {1861-4728}, doi = {10.1002/asia.202000807, Early Access Date = SEP 2020}, author = {Yadav, Sandeep and Kumar, Rohit and Raj, K. Vipin and Yadav, Prashant and Vanka, Kumar and Sen, Sakya S.} } @article {46595, title = {Mixed metal oxide: a new class of catalyst for methanol activation}, journal = {Applied Surface Science}, volume = {534}, year = {2020}, month = {DEC}, pages = {147449}, type = {Article}, abstract = {

In this work, we propose a mixed metal oxide as a catalyst and demonstrate it{\textquoteright}s ability to not only activate the MeOH molecule upon adsorption but also dissociate O-H and one of it{\textquoteright}s C-H bonds. MeOH activation is compared on two prominent facets of ZnAl(2)O(4 )viz. (2 2 0) and (31 1). While spontaneous O-H bond dissociation is observed on both facets, C-H bond dissociates only on the (3 1 1) surface. Multiple factors like atomic arrangement and steps on the surface, coordination of surface atoms, and their effective charges have a combined effect on MeOH activation. The (3 1 1) surface offers higher catalytic activity in comparison with (2 2 0) surface. Having a stepped surface, availability of multiple sites, and variation in the charge distribution are some of the reasons for better catalytic performance of (3 1 1) facet. Effect of orientation of MeOH with respect to the surface adds both, information and complexity to the problem. Observations pertinent to understanding this effect are also reported. A detailed analysis of atomic arrangement on the two surfaces provides a rationale as to why MeOH gets dissociated spontaneously on the mixed metal oxide. The promising results reported here opens up a new class of catalyst for research.

}, keywords = {DFT, MeOH, Spontaneous dissociation, ZnAl2O4}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2020.147449}, author = {Mehta, Shweta and Agarwal, Sheena and Kenge, Nivedita and Mekala, Siva Prasad and Patil, Vipul and Raja, T. and Joshi, Kavita} } @article {47653, title = {Glycerol-triazole conjugated rhodamine as colorimetric and fluorimetric sensor for Cu2+}, journal = {ChemistrySelect}, volume = {6}, year = {2021}, month = {SEP}, pages = {9288-9292}, type = {Article}, abstract = {{A glycerol-triazole tethered rhodamine based colorimetric and fluorimetric sensor 3 {\textquoteleft},6 {\textquoteleft}-bis(diethylamino)-2-(((1-(1,3-dihydroxypropan-2-yl)-1H-1,2,3-triazol-4 -yl)methylene)aminospiro [isoindoline-1,9 {\textquoteleft}-xanthen]-3-one (L1) is designed and synthesized for the selective recognition of Cu2+ ion. The sensor L1 allows naked eye detection of Cu2+ ion with a fast response (<1 min). Among the various metal ions tested, the sensor L1 shows selective binding with Cu2+ through turn-on fluorescence mechanism. The sensor shows 1 : 2 binding stoichiometry with binding constant}, keywords = {Cu2+ Sensor, DFT, Glycerol, Rhodamine B, Triazole}, issn = {2365-6549}, doi = {10.1002/slct.202102145}, author = {Verma, Abhishek and Gahlyan, Parveen and Bawa, Rashim and Dash, Soumya Ranjan and Prasad, Ashok K. and Kumar, Rakesh} } @article {46630, title = {Insights into the nature of self-extinguishing external donors for ziegler-natta catalysis: a combined experimental and DFT study}, journal = {ChemCatChem}, volume = {13}, year = {2021}, month = {JAN }, pages = {674-681}, type = {Article}, abstract = {

Developing donors for Ziegler-Natta (ZN) catalysis to control the polymerization reaction and produce polymers with desirable properties has always been challenging due to the multi-component nature of the catalytic systems. Here, we have developed a new synthetic protocol for making two external donors, D-1 (2,2,2-trifluoroethyl myristate) and D-2 (2,2,2-trifluoroethyl palmitate) that show self-extinguishing properties, followed by a systematic DFT study to understand this peculiar property of these donors. D-1 and D-2 can undergo parallel reactions with aluminum and titanium species present in the system to produce ketones and aldehydes, which are poisons for ZN catalytic systems, thus explaining their self-extinguishing nature. The non-covalent interaction between the long alkyl chain of the donors with the surface plays a vital role in determining the donors {\textquoteleft} self-extinguishing nature. There is a significant thermodynamic preference for the binding of the donor with the longer alkyl chain at the titanium center. The current work, therefore, provides interesting insights into how self-extinguishing donors function in ZN catalytic systems.

}, keywords = {DFT, donors, non-covalent interactions, self-extinguishing, Ziegler-Natta catalysis}, issn = {1867-3880}, doi = {10.1002/cctc.202001493, Early Access Date = NOV 2020}, author = {Vipin Raj, K. and Kumawat, Jugal and Dhamaniya, Sunil and Subaramanian, Murugan and Balaraman, Ekambaram and Kumar Gupta, Virendra and Vanka, Kumar and Grubbs, Robert H.} } @article {47627, title = {Mechanistic investigations on the catalytic transfer hydrogenation of lignin-derived monomers over Ru catalysts: theoretical and kinetic studies}, journal = {ACS Sustainable Chemistry \& Engineering}, volume = {9}, year = {2021}, month = {OCT}, pages = {14040-14050}, type = {Article}, abstract = {The hydrodeoxygenation (HDO) reaction of oxygenated compounds such as lignin-derived phenolics is well studied using molecular H-2 as a hydrogen source, yet the use of high pressures discourages its use on an industrial scale. As an alternative, the catalytic transfer hydrogenation (CTH) pathway provides in situ hydrogenation species, which reduces the need for the high-pressure infrastructure required when molecular hydrogen is used. Nevertheless, this strategy is scantly studied, and in lieu with this, herein we report the kinetic and mechanistic investigations of the CTH strategy for the HDO of guaiacol, phenol, anisole veratrole, and eugenol to their respective products. For potential commercialization purposes, low loading of metal, milder reaction conditions, and high selectivity toward desired products with a high H/C ratio were considered while designing catalysts (0.5 wt \% Ru on SiO2-Al2O3, SiO2, Al2O3-acidic, Al2O3-basic, and Al2O3-neutral) for these reactions. As high as 74\% cyclohexanol yield from guaiacol was achieved at 225 degrees C in the presence of isopropyl alcohol (IPA) as the hydrogen source and over the Ru/Al2O3-acidic catalyst reduced at 150 degrees C. A detailed kinetic study is carried out to understand the interaction of the substrate and intermediates with the catalyst and the influence of reaction parameters on the product formation. It was observed that the cisisomer of 2-methoxycyclohexanol rapidly undergoes further conversion than the trans-isomer. The experimental observations are substantiated through density functional theory (DFT) studies on Ru(0001) and guaiacol molecule complexes. DFT studies indicate that the adsorption of the cis-isomer is more exothermic as compared to that of the trans counterpart, and the underlying electronic factors are elucidated using charge density difference and density of states plots.}, keywords = {catalytic transfer hydrogenation, Cyclohexanol, DFT, Hydrodeoxygenation, kinetics, lignin monomers, Supported metal catalysts}, issn = {2168-0485}, doi = {10.1021/acssuschemeng.1c02942}, author = {Khan, Tufeil Sartaj and Singh, Dheerendra and Samal, Pragnya Paramita and Krishnamurty, Sailaja and Dhepe, Paresh Laxmikant} } @article {47661, title = {Substrate augmented catalytic activity towards NRR: a case study of Li doped Al clusters on defective graphene}, volume = {566}, year = {2021}, month = {NOV}, pages = {150586}, type = {Article}, abstract = {Density Functional Theory (DFT) based methods are applied to examine the potential of lithium doped aluminium clusters consisting of 3-13 atoms for dinitmgen molecule activation in terms of N N bond length, redshift in N N bond stretching frequency, nitrogen interaction energy and frontier molecular orbitals analysis. The present work highlights the role of monovacant C-3 defective graphene as a support in fine tuning the catalytic activity of Li doped Al clusters for reduction of N-2. Fundamental insights to synergic binding of clusters with defective graphene is brought out and its role in enhancing activation of dinitmgen molecule is explained. Supported Aln-1Li clusters with six or more atoms are noted to be more active towards N-2 molecule activation as compared to the clusters without support. Dinitrogen molecule undergoes a maximum bond elongation of 1.56 angstrom corresponding to redshift of 1690 cm(-1) on Al7Li@graphene and Al12Li@graphene. This is maximum value reported in context of activation for N-2 molecule till date.}, keywords = {Al clusters, Al12Li, C-3 defective graphene, DFT, Li Doping, N-2 activation, Red-shift}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2021.150586}, author = {Samal, Pragnya Paramita and Poonam and Krishnamurty, Sailaja} } @article {47654, title = {Unsymmetrical sp(2)-sp(3) disilenes}, journal = {Angewandte Chemie-International Edition}, volume = {60}, year = {2021}, month = {SEP }, pages = {20706-20710}, type = {Article}, abstract = {Disilenes with differently coordinated silicon atoms are not known. Here, we have shown the high yield synthesis of a range of disilenes (2-4 and 6) upon reaction of a hypersilyl silylene PhC(NtBu)(2)SiSi(SiMe3)(3) (1) with aliphatic chlorophosphines. The most striking characteristic of these disilenes is the presence of two differently coordinated Si atoms (one is three-coordinated, the other four-coordinated). The analogous reaction with Ph2PCl did not afford the desired disilene, but, surprisingly, led to the first tetraphosphinosilane (8). DFT calculations were performed to understand the bonding in disilenes and differences in reactivity of the complexes.}, keywords = {chlorophosphine, DFT, disilene, hypersilylsilylene}, issn = {1433-7851}, doi = {10.1002/anie.202107847}, author = {Bisai, Milan Kumar and Das, Tamal and Vanka, Kumar and Gonnade, Rajesh G. and Sen, Sakya S.} } @article {48193, title = {Doped 2D VX2 (X = S, Se, Te) monolayers as electrocatalysts for ammonia production: a DFT based study}, journal = {Applied Surface Science}, volume = {602}, year = {2022}, month = {NOV}, pages = {154401}, type = {Article}, abstract = {

Electrocatalytic nitrogen fixation under ambient conditions on vanadium dichalcogenides (VX2) with non-metal dopants has been explored herein. Understanding the interface chemistry, inherent electronic and acute synergistic nature of non-metal dopants on two unique phases of VX2 has been meticulously explored through a scrutiny of several non-metal atoms as catalytic centers. The efficacity of N-2 chemisorption and N-N bond activation has been implemented as crucial parameters to realize boron and carbon doped VX2 monolayers to be electrocatalytically active for nitrogen reduction reaction (NRR). Detailed investigation on the NRR mechanism brings out the pivotal role of thermodynamic favourability for product formation obtained from Gibbs free energy differences. The charge transfer on N and pi-pi* orbital hybridization and electron {\textquoteleft}{\textquoteleft}donor-acceptor {\textquoteleft}{\textquoteleft} mechanism between the non-metal and N-2 has been found to modulate the electrocatalytic barrier for NRR on VX2 monolayers. This study proposes boron doped VS2 as an efficient chemically feasible, earth abundant sustainable electrocatalyst for NRR with an overpotential as low as 0.06 eV.

}, keywords = {1T and 2H phases, DFT, electrocatalysts, Nitrogen Reduction Reaction, Non metal dopants, Vanadium dichalcogenides}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2022.154401}, author = {Maibam, Ashakiran and BabaRao, Ravichandar and Krishnamurty, Sailaj A.} } @article {48036, title = {From molecular adsorption to decomposition of methanol on various ZnO facets: a periodic DFT study}, journal = {Applied Surface Science}, volume = {602}, year = {2022}, month = {NOV}, pages = {154150}, type = {Article}, abstract = {

Methanol is an interesting and important molecule to study because of its potential to replace existing fuels. It is also a prominent hydrogen source which can be used to generate hydrogen in-situ. ZnO is widely used as catalyst in synthesis of methanol from CO2 at industrial scale. In this work, we demonstrate that the same catalyst could be used for MeOH decomposition. We have investigated interaction of methanol with various flat and stepped facets of ZnO by employing Density Functional Theory (DFT). Two flat [(10(1)overbar 0) and (11(2)overbar 0)] and two stepped [(10(1)overbar 3) and (11(2)overbar 2)] facets are studied in detail for methanol adsorption. Chemisorption of MeOH with varying strength is common to all four facets. Most importantly spontaneous dissociation of O-H bond of methanol is observed on all facets except (11(2)overbar 0). Our DFT calculations reveal that molecular adsorption is favored on flat facets, while dissociation is favored on step facets. Also, (10(1)overbar 0) facet undergoes substantial reconstruction upon MeOH adsorption. Activation of C-H bond along with strengthening of C-O bond on ZnO facets suggest partial oxidation of methanol. With our DFT investigations, we dig deeper into the underlying electronic structure of various facets of ZnO and provide rationale for the observed facet dependent interaction of ZnO with MeOH.

}, keywords = {DFT, MeOH, Surface interactions, ZnO}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2022.154150}, author = {Mehta, Shweta and Joshi, Kavita} } @article {48061, title = {Looking beyond adsorption energies to understand interactions at surface using machine learning}, journal = {ChemistrySelect}, volume = {7}, year = {2022}, month = {OCT}, pages = {e202202414}, type = {Article}, abstract = {

Identifying factors that influence interactions at the surface is still an active area of research. In this work, the importance of analyzing bond length activations (BLact) along with adsorption energies (E-a) while interpreting Density Functional Theory (DFT) results is emphasized. Investigating adsorption of different small molecules, such as O-2, N-2, CO, and CO2, on commonly studied facets ((100), (110), and (111)) of seven fcc transition metal surfaces (M=Ag, Au, Cu, Ir, Rh, Pt, and Pd) demonstrates the missing linear correlation between E-a and BLact. Further, tree based Machine Learning (ML) models reinforce the missing linear correlation between the two parameters and also highlight the importance of analyzing both to develop a better understanding of adsorption at surfaces. The best performing Random Forest models have a mean absolute error (MAE) of 0.19 eV for E-a prediction, and even lower MAE of 0.012 angstrom for BLact prediction. While often d-band center is correlated with E-a, our observations show that infact the d-band center has a better correlation with BLact. These observations emphasizes the role of BLact in gaining a fuller picture for catalysis. The fact that the factors responsible for BLact is a lesser-explored subject adds to the novelty of the findings.

}, keywords = {Adsorption energy, Bondlength activation, catalysis, DFT, machine learning}, issn = {2365-6549}, doi = {10.1002/slct.202202414}, author = {Agarwal, Sheena and Joshi, Kavita} } @article {47769, title = {Regioselectivity in metalloradical catalyzed C-H bond activation: a theoretical study}, journal = {Journal of Organometallic Chemistry}, volume = {957}, year = {2022}, month = {JAN }, pages = {122179}, type = {Article}, abstract = {Pure quantum mechanical calculations were performed to find out the origin of regioselectivity under the metalloradical catalysis (MRC) by Co(II)-porphyrin, which showed regioselectivity is the inherent property of the aminyl radical generated from the sulfamoyl azide substrate. Different conformational analysis for the transition state from alpha-Co-III-aminyl radical to zeta-Co-III-alkyl radical formation have been studied to find out the most stable conformation for the preferable selectivity. The outcome of our study completely agrees with the reported experimental results. (C) 2021 Elsevier B.V. All rights reserved.}, keywords = {C-H activation, DFT, Metalloporphyrin, Metalloradical, Regioselectivity}, issn = {0022-328X}, doi = {10.1016/j.jorganchem.2021.122179}, author = {Mukherjee, Anirban and Singh, Ritesh and Mane, Kishor D. and Das, Gourab Kanti} } @article {47656, title = {Role of facet in the competitive pathway of ethylene epoxidation}, journal = {Surface Science}, volume = {716}, year = {2022}, month = {FEB}, pages = {121954}, type = {Article}, abstract = {Ethylene epoxide (EtO) is used as raw material for a broad range of products from pharmaceuticals and plastics to paints and adhesives. Although the reaction of ethylene interacting with preadsorbed oxygen on Ag surface is known for decades, the underlying mechanism of EtO formation is not completely understood. Successful investigation of oxametallacycle (OMC) intermediate common to selective as well as non-selective pathways has ensured at least 50\% selectivity. The current study brings out the electronic signatures of distinct conformers of OMC stabilised on two different facets of Ag viz. (100) and (111). There are subtle differences between OMC conformers observed on these two facets with near-eclipsed on Ag(100) and near-staggered on Ag(111). A detailed analysis of Ag-O, C-O, C-C, and Ag-C interactions along with projected Density of States (pDOS) and projected Crystal Orbital Hamilton Population (pCOHP) imply towards ring closure on Ag(100) and hydrogen transfer on Ag(111). Finally, our understanding based on electronic and structural signatures are backed up by activation barriers computed through NEB calculations. Activation barrier for EtO is lower on (100) as compared to (111) facet. Thus, our study sheds light on how these differences between OMC affect the selectivity towards EtO.}, keywords = {Ag(100), Ag(111), DFT, epoxidation, Ethylene Oxide (EtO), OMC}, issn = {0039-6028}, doi = {10.1016/j.susc.2021.121954}, author = {Nair, Aathira and Kenge, Nivedita and Joshi, Kavita} } @article {48368, title = {Structure-property insights into chiral thiophene copolymers by direct heteroarylation polymerization}, journal = {European Polymer Journal}, volume = {181}, year = {2022}, month = {DEC }, pages = {111676}, type = {Article}, abstract = {

Chiral thiophene copolymers with fluorene as co monomer are designed having N-Boc-L-glutamic acid-1-tert-butyl ester as a chiral substituent located either on the thiophene unit or the fluorene unit with varying spacer length. The atom-economic direct heteroarylation polymerization (DHAP) method is utilized for the polymerization. Gibb{\textquoteright}s free energy (delta G) for polymerization determined using DFT calculations indicate difficulty in achieving high molar mass when the bulky chiral substituents are attached through short spacer to the backbone. The experimental observations are in agreement with the theoretical calculations with no polymer-ization or very low molar mass sticky compounds obtained for reactions with predicted + \& UDelta;G values. Structure -property relationship are compared for two chiral polymers -P4 and P5 having the chiral substitution on thiophene and fluorene units respectively. No CD signal is observed in THF-a good solvent where the polymers are molecularly dissolved. Intense bisignated CD signal is observed for both polymers upon addition of methanol - a poor solvent, to their THF solution. The bisignate CD signal with maxima at lower wavelength and inflection point associated with the pi-pi* absorption band is characteristic of exciton coupling between polymer chains in a left handed helical orientation. Small differences are observed in the intensity of the CD signal for the polymers P4 and P5 highlighting the impact of steric hindrance of bulky pendant groups on polymer conformation. DHAP is an atom economic polymerization procedure that can be gainfully utilized for developing chiral conjugated polymers.

}, keywords = {chiral, DFT, Direct heteroarylation polymerization, Gibb?s free energy, Steric Hindrance}, issn = {0014-3057}, doi = {10.1016/j.eurpolymj.2022.111676}, author = {Nikam, Shrikant B. and Singh, Chandrodai Pratap and Krishnamurty, Sailaja and Asha, S. K.} } @article {48695, title = {Electronic fingerprints for diverse interactions of methanol with various Zn-based systems}, journal = {Surface Science}, volume = {736}, year = {2023}, month = {OCT}, pages = {122350}, type = {Article}, abstract = {

We have investigated various Zn-based catalysts for their interaction with methanol (MeOH). MeOH is one of the most critical molecules being studied extensively, and Zn-based catalysts are widely used in many industrially relevant reactions involving MeOH. We note that the same element (Zn and O, in the present study) exhibits different catalytic activity in different environments. The changing environment is captured in the underlying electronic structure of the catalysts. In the present work, we compared the electronic structure of Zn-based systems, i.e., ZnAl2O4 and ZnO along with oxygen preadsorbed Zn (O-Zn) and metallic Zn. We demonstrate the one-to-one correlation between the pDOS of the bare facet and the outcome of that facet{\textquoteright}s interaction (i.e. either adsorption or dissociation of MeOH) with MeOH. These findings would pave the way towards the in-silico design of catalysts.

}, keywords = {DFT, Electronic properties, Methanol, Zn-based systems, ZnO}, issn = {0039-6028}, doi = {10.1016/j.susc.2023.122350}, author = {Mehta, Shweta and Joshi, Kavita} } @article {48755, title = {Enhancing diradical character of chichibabin{\textquoteright}s hydrocarbon through fluoride substitution}, journal = {ChemPlusChem}, volume = {88}, year = {2023}, month = {AUG}, pages = {e202300273}, type = {Article}, abstract = {

In this work, 5-SIDipp [SIDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene] (1) derived Chichibabin{\textquoteright}s hydrocarbon with an octafluorobiphenylene spacer (3) has been reported. The addition of two equivalents of 5-SIDipp with decafluorobiphenyl in presence of BF3 gives the double C-F bond activated imidazolium salt with two tetrafluoroborate anions, 2. Further reduction of 2 gives the fluorine substituted 5-SIDipp based Chichibabin{\textquoteright}s hydrocarbon, 3. Quantum chemical calculations suggested a singlet state of 3 with a singlet-triplet energy gap (?ES-T) of 3.7 kcal mol(-1), which is substantially lower with respect to the hydrogen substituted NHC-based Chichibabin{\textquoteright}s hydrocarbons (10.7 kcal mol(-1), B3LYP). As a result, the diradical character (y) of 3 (y=0.62) is also noticeably higher than the hydrogen substituted CHs (y=0.41-0.43). The ?ES-T was found to be higher in CASSCF (22.24 kcal mol(-1)) and CASPT2 (11.17 kcal mol(-1)) for 3 and the diradical character (d) is 44.6 \%.

}, keywords = {C-F Bond Activation, Chichibabin \& PRIME, DFT, N-Heterocyclic carbene, s Hydrocarbon}, issn = {2192-6506}, doi = {10.1002/cplu.202300273}, author = {Kundu, Gargi and Dash, Soumya Ranjan and Kumar, Ravi and Vanka, Kumar and Ghosh, Aryya and Sen, Sakya S.} } @article {48774, title = {Hydrogen from catalytic non-thermal plasma-assisted steam methane reforming reaction}, journal = {International Journal of Hydrogen Energy}, volume = {48}, year = {2023}, month = {JUL}, pages = {24328-24341}, type = {Article}, abstract = {

Steam methane reforming reaction was carried out in a dielectric barrier plasma reactor. A systematic study is conducted to understand the influence of input power, flow rate, and water for the conversion, yield, and selectivity of the reaction over strategically designed catalysts. In particular, the production rate and selectivity of the products (H2, CO and C2 hydrocarbons) are monitored. CeO2 was used as packing material, mixed with oxides of manganese or copper and their combination. The optimum Cu/CeO2 catalyst illustrated the production rate of 248.7 mmolg-1h-1 and 11.25 mmolg-1h-1 for H2, and CO, respectively at specific energy input of 19.8 JL-1. DFT calculations exhibit apparent change in electronic structure of the CeO2 after inclusion of oxides of manganese and copper that enhance interaction with methane. Based on these findings, a plausible mechanism is elucidatedSteam methane reforming reaction was carried out in a dielectric barrier plasma reactor. A systematic study is conducted to understand the influence of input power, flow rate, and water for the conversion, yield, and selectivity of the reaction over strategically designed catalysts. In particular, the production rate and selectivity of the products (H2, CO and C2 hydrocarbons) are monitored. CeO2 was used as packing material, mixed with oxides of manganese or copper and their combination. The optimum Cu/CeO2 catalyst illustrated the production rate of 248.7 mmolg-1h-1 and 11.25 mmolg-1h-1 for H2, and CO, respectively at specific energy input of 19.8 JL-1. DFT calculations exhibit apparent change in electronic structure of the CeO2 after inclusion of oxides of manganese and copper that enhance interaction with methane. Based on these findings, a plausible mechanism is elucidated which can help to design catalyst for other applications in non-thermal plasma atmosphere. \& COPY; 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

}, keywords = {DFT, Dielectric barrier discharge, Non-thermal plasma, selectivity, Specific energy input, Steam methane reforming}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2023.03.281}, author = {Bajpai, Abhinav and Mehta, Shweta and Joshi, Kavita and Kumar, Sushant} } @article {48456, title = {Understanding the thermal stability of a 3d, 4d, and 5d element doped aluminium nanocluster through BOMD simulations}, journal = {Molecular Simulation}, volume = {49}, year = {2023}, month = {FEB}, pages = {245-250}, type = {Article}, abstract = {

Endohedrally doped atomic clusters have generated considerable interest among computational chemists on account of their tunable chemical properties that mimic a super atom. Such endohedrally doped clusters have also been experimentally realised in the more recent past. The present work explores the practical existence of 3d, 4d and 5d doped aluminium clusters, more specifically doped Al13 cluster, by evaluating systematically their structural stability through the first principle molecular dynamical simulations. Born-Oppenheimer Molecular Dynamics (BOMD) simulations have been carried out on Al12X atomic clusters where X = Ti, V, Fe, Co, Ni, Cu, Zn, Y, Mo, Ru, Rh and W are in endohedral position. The thermal stability of such endohedrally doped clusters is quantified through parameters such as delta(rms), MSD and is an element of(pro). Electronic structure calculations reveal that endohedral doping of only Rh, Cu and Zn is preferred in the Al-13 cluster. Other dopants prefer to remain on the surface positions. However, finite temperature calculations reveal that the Al12Zn cluster undergoes surface modifications from 300K leading to a distorted icosahedral structure. Al12Cu cluster in quartet spin state is the only thermally stable cluster with Cu remaining in the endohedral position and structure retaining icosahedral confirmation till 700K.

}, keywords = {Al-13 atomic cluster, BOMD simulations, DFT, Endohedral doping, super atom}, issn = {0892-7022}, doi = {10.1080/08927022.2022.2153151}, author = {Samudre, Nikhil S. and Singh, Chandrodai Pratap and Krishnamurty, Sailaja} } @article {48997, title = {4-aminoantipyrine linked bis-1,2,3-triazole based probes for Cu(II) sensing}, journal = {Journal of Molecular Structure }, volume = {1297}, year = {2024}, month = {FEB }, type = {Article}, abstract = {

Herein, two molecular probes of 4-aminoantipyrine-linked bis-1,2,3-triazoles have been studied for metal ion sensing applications. The crystal structure of one of the probes named as 4,4 {\textquoteleft}-((4,4 {\textquoteleft}-(((1,5-dimethyl- 3- oxo- 2- phenyl- 2,3- dihydro- 1H- pyrazol- 4-yl) azanediyl) bis(methylene))bis(1H-1,2,3-triazole-4,1-diyl))bis(methylene))dibenzonit rile (3b) crystalizes in Monoclinic crystal system in P 1 21/n 1 space group. Both probes responded more strongly and selectively to Cu(II) than other tested metal ions (K+, Na+, Mg2+, Ba2+, Ca2+, Cr3+, Mn2+, Co2+, Zn2+, Cd2+, Ni2+, Hg2+, and Pb2+). Job{\textquoteright}s plot suggested a 1:1 stoichiometric ratio of ligand and metal ion. Both probes showed an association constant of 2.48 x 10(3) M-1 and 3.73 x 10(3) M-1 through Benesi-Hildebrand (B-H) plot. The geometries of both probes and their complexes were optimized by DFT using B3LYP/6-311 G(d,p) and B3LYP/LanL2DZ basis sets, and properties were supported by Mulliken atomic charge and Molecular electrostatic potential. Molecular docking on both probes and their complexes with Type-II topoisomerases(PDB ID: 4G0V) protein was conducted to foretastes anticancer activity.

}, keywords = {2, 3-Triazole, 4-aminoantipyrine, and Molecular docking, Bis-1, Cu2+ Sensor, DFT, X-ray crystallography}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2023.136995}, author = {Lal, Bajrang and Kumar, Sachin and Tittal, Ram Kumar and Singh, Gurleen and Singh, Jandeep and Ghule, Vikas D. and Mathpati, Ramling S. and Sabane, Jagjivan K.} } @article {49417, title = {Designing of imine thiophene-ligated metal-complexes and implication in ethylene polymerization}, journal = {Journal of Macromolecular Science Part A-Pure and Applied Chemistry}, year = {2024}, month = {SEP}, type = {Article; Early Access}, abstract = {

Polyethylene is the single largest volume polymer produced globally using Ziegler-type catalysts. Numerous modifications have been reported in search of a better catalyst that can control molecular weight, polydispersity, and branching. In our attempts to identify a suitable imine thiophene-ligated chromium complex, we examined 9 different titanium complexes computationally. The DFT investigations considered barriers for insertion, propagation, and termination by beta-H elimination or chain transfer, and identified N-(4-methoxyphenyl)-2-phenyl-1-(thiophen-2-yl)ethan-1-imine(L9) as the most suitable ligand. Subsequently, L9 was prepared in good yield (70\%) by condensing 2-phenyl-1-(thiophen-2-yl)ethan-1-one with 4-methoxyaniline. Ligand L9 was treated with early transition metal precursors (Ti, Cr, Zr) to generate a homogenous catalyst. The identity of these catalysts was unambiguously ascertained using a combination of NMR, ICP, FT-IR, UV-Vis spectroscopy, and ESI-MS. The performance of L9-ligated titanium complex [Cat.1] was examined in ethylene polymerization using MMAO as a co-catalyst. Insertion of ethylene was tracked using high-pressure NMR experiments and Cat.1 was found to be active in the polymerization. Ethylene polymerization conditions were optimized to obtain high activity and molecular weight polyethylene. The chromium complex [Cat.2] outperformed the Ti and Zr-derived catalysts with the highest TOF of 6294 mol of PE/mol of Cr/h. Cat.2 produced high molecular weight, high-density polyethylene.

}, keywords = {Cr-complexes, DFT, high-density polyethylene, Imine thiophene ligand, Polyethylene}, issn = {1060-1325}, doi = {10.1080/10601325.2024.2409753}, author = {Shaikh, Maulali H. and Ramekar, V. Rohan and Jawoor, Shailaja and Dash, Soumya R. and Birajadar, Rajkumar S. and Pawal, Sandip B. and Thenmani, Nandakumar and Vanka, Kumar and Chikkali, Samir H.} } @article {49035, title = {Exploring the catalytic potential of Mg-Cu alloys for enhanced activity toward CO2 hydrogenation}, journal = {Molecular Catalysis }, volume = {556}, year = {2024}, month = {MAR }, type = {Article}, abstract = {

CO2, a well-known greenhouse gas, is a potential raw material that can produce various chemicals. Dissociation of CO2 to CO or hydrogenation to formate (HCOO*) or carboxyl (COOH*) intermediate is crucial in determining the reaction pathway for CO2 conversion. In this work, we demonstrate that alloys of Mg-Cu exhibit greater activity toward activation and hydrogenation of CO2 than transition metal alloys reported so far. Two different compositions of Mg-Cu, namely Mg2Cu and MgCu2, have been studied using periodic Density Functional Theory (DFT). Our investigations reveal that CO2 chemisorbs on both intermetallic alloys. Coadsorption of CO2 with H2O leads to the spontaneous formation of COOH* over Mg2Cu(224), whereas a negligible barrier (0.04 eV) is observed for MgCu2(311). HCOO* formation has a barrier of 0.34 eV and 0.42 eV on Mg2Cu(224) and MgCu2(311), respectively. Dissociation of CO2 to CO is kinetically unfavourable on both compositions of Mg-Cu. We provide a rationale for the observed activity by analyzing the electronic structure. Notably, the spontaneous hydrogenation of CO2 makes earth -abundant metals suitable candidates for alloying that await experimental verification.

}, keywords = {CO2 hydrogenation, DFT, Mg2Cu, MgCu2}, issn = {2468-8231}, doi = {10.1016/j.mcat.2024.113839}, author = {Thakkar, Kavita and Joshi, Kavita} } @article {49310, title = {From digital blueprint to chemical reality: methanol to formaldehyde at ambient conditions}, journal = {Applied Surface Science}, volume = {669}, year = {2024}, month = {OCT }, pages = {160527}, type = {Article}, abstract = {

Partial oxidation of methanol to value added product presents an intriguing yet challenging process. Among these products, formaldehyde is the simplest and one of the most vital aliphatic aldehydes, which has extensive application across various domains. Industrially, silver and iron-molybdenum oxides are used as catalysts for the conversion of methanol to formaldehyde at elevated temperatures (600 degrees C and 250-400 degrees C, respectively). However, in this computational and experimental study, we have demonstrated the efficacy of ZnO as a catalyst. Notably, in the presence of ZnO, methanol readily converts to formaldehyde even under ambient conditions. We employed periodic density functional theory (DFT) to explore (10 1 1) facet of ZnO to elucidate its interaction with methanol. Our comprehensive analysis identified the most active facet (10 1 1) involved in the spontaneous conversion of methanol to formaldehyde. Subsequently, experimental validation supported our theoretical findings, demonstrating the conversion of methanol to formaldehyde with 100\% selectivity at room temperature and atmospheric pressure in the presence of ZnO. This study exemplifies the pivotal role of theory in catalyst design.

}, keywords = {DFT, Formaldehyde, MeOH, ZnO}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2024.160527}, author = {Mehta, Shweta and Kasabe, Mirabai and Umbarkar, Shubhangi B. and Joshi, Kavita} } @article {49404, title = {Insights on prussian blue analogue cathode material engineered with polypyrrole surface protection layer for aqueous rechargeable zinc metal battery}, journal = {Small}, year = {2024}, month = {NOV}, type = {Article; Early Access}, abstract = {

One of the key intricacies against using Prussian blue analogues (PBAs) in aqueous batteries is their gradual dissolution in aqueous electrolytes, resulting in inadequate cycling stability. Besides, the rate capability of PBAs is limited due to their poor electrical conductivity. To overcome these challenges, it is essential to tune the physical and chemical properties of PBAs at the nano regime without affecting the inherent charge storage properties, especially at high-voltage operating conditions. Through this work, a strategy is demonstrated to enhance the electrochemical performance of vanadium-based PBA (V-PBA) by surface engineering using a conducting polymer nano-skin (V-PBA/PPy) for aqueous zinc metal batteries. The polypyrrole (PPy) nano-skin over the V-PBA nanoparticles acts as an electron percolation path to ameliorate the poor electronic conductivity of the otherwise pristine V-PBA. Interestingly, the V-PBA with an optimized polypyrrole coating (V-PBA/PPy-2) exhibits an enhanced specific capacity (173 mAh g-1 at 0.10 A g-1) than the pristine V-PBA counterpart (80 mAh g-1) and 85\% capacity retention up to 500 cycles. The DFT calculation confirms the synergistic interaction between PPy and V-PBA and the presence of PPy favors the adsorption of Zn.

}, keywords = {aqueous rechargeable zinc metal battery, DFT, polypyrrole coating, Prussian blue analogue, surface protection layer}, issn = {1613-6810}, doi = {10.1002/smll.202409947}, author = {Puthiyaveetil, Priyanka Pandinhare and Nair, Aathira and Dilwale, Swati and Kurian, Maria and Joshi, Kavita and Kurungot, Sreekumar} } @article {48931, title = {Single-atom alloys of Cu(211) with earth-abundant metals for enhanced activity towards CO2 dissociation}, journal = {Journal of Molecular Graphics and Modelling }, volume = {126}, year = {2024}, month = {JAN}, type = {Journal Article}, abstract = {

CO2, a byproduct from various industrial reactions, must not be released into the atmosphere and should be managed through capture, conversion, and utilization. The first step in converting CO2 into valuable products is to break the C-O bond. This work focuses on designing Single Atom Catalysts (SACs) by doping Cu(211) surface with 13 different s, p, and d block elements with an aim to minimize the activation barrier for C-O bond cleavage. Our work demonstrates that SACs of Mg/Al/Pt@Cu(211) favor CO2 chemisorption compared to Cu(211) where CO2 physisorbs. The barrier for CO2 dissociation is lowest for Mg@Cu(211) and it increases in the order Mg@Cu(211) \< Al@Cu(211) \< Pt@Cu(211) \< Zn@Cu(211) \< Ga@Cu(211) \< Cu@Cu(211) \< Pd@Cu(211). These findings suggest that doping Cu(211) with earth-abundant metal like Mg can potentially be a viable catalyst for CO2 conversion, providing a promising solution to reduce carbon footprint and mitigate climate change.

}, keywords = {CO2, Cu(211), DFT, Single atom catalysts}, issn = {1093-3263}, doi = {10.1016/j.jmgm.2023.108656}, author = {Thakkar, Kavita and Joshi, Kavita} } @article {49033, title = {What leads to direct epoxidation? an exhaustive DFT investigation of electrophilic oxygen mediated epoxidation of ethylene on Ag(100)}, journal = {Computational Materials Science }, volume = {239}, year = {2024}, month = {APR}, type = {Article}, abstract = {

Extensive research has contributed to a better understanding of the commercially important epoxidation reaction. Selectivity, a crucial aspect of this reaction, has received significant attention in both experimental and theoretical investigations. However, a consensus regarding the role of electrophilic oxygen in epoxidation is yet to be reached. The present study is a theoretical examination of the prerequisites necessary for direct epoxidation to occur on the Ag(100) surface, at varied monolayer concentrations. Additionally, the study investigates the characteristics of various oxygen species interacting with ethylene to promote the direct epoxidation pathway. Based on the effective charges and projected density of states (pDOS) analysis, three oxygen variants were identified on the Ag(100) surface: atomic oxygen, dissociatively adsorbed molecular oxygen, and O 3 . The investigation reveals that all oxygen species, despite their physical and electronic differences, are electrophilic and undergo direct epoxidation. This work provides insights into the complex nature of epoxidation reaction and discusses electronic factors influencing the selective oxidation route on different Ag-O complexes.

}, keywords = {Ag(100), DFT, Direct epoxidation, Electrophilic oxygen, Ethylene Oxide (EtO), OMC}, issn = {0927-0256}, doi = {10.1016/j.commatsci.2024.112959}, author = {Nair, Aathira and Joshi, Kavita} } @article {49611, title = {Design and synthesis of PtPdNiCoMn high-entropy alloy electrocatalyst for enhanced alkaline hydrogen evolution reaction: a theoretically supported predictive design approach}, journal = {Advanced Functional Materials}, volume = {35}, year = {2025}, month = {APR}, type = {Article}, abstract = {

Electrocatalytic hydrogen generation requires a cutting-edge, multifunctional electrocatalyst with abundant active sites to drive multielectron transfer reactions. High entropy alloys (HEA) are complex five or more-element alloy systems with high configurational entropy which makes them unique materials for next-generation electrocatalysts. Here, in this work, based on new screening guidelines for catalyst selections that combine density-functional theory calculated Gibbs formation-enthalpy with bond length and electronegativity variance, a novel HEA electrocatalyst consisting of five elements, namely, Pt, Pd, Ni, Co, and Mn is designed. By simple room temperature electrodeposition, the designed catalyst is prepared and its hydrogen evolution reaction (HER) is explored and validated through experimental and theoretical approaches. The HEA demonstrated a superior HER activity with an overpotential of 22.6 mV at -10 mA cm-2 which outperforms Pt/C commercial catalyst. No evident degradation of the material is detected even after 100 hours of continuous operation under high current density. Moreover, the HEA has shown exceptional performance in harsh electrolyte conditions such as in simulated seawater and actual seawater. Remarkably, the density-functional theory calculated small Gibbs formation-enthalpy (approximate to 0 eV) compared to Pt/C places the new HEA near the apex of Trasatti{\textquoteright}s model of Volcano plot, which is also suggestive of superior HER activity.

}, keywords = {DFT, electrocatalysts, Electronic Structure, HER, high-entropy alloys}, issn = {1616-301X}, doi = {10.1002/adfm.202418644}, author = {Chandran, M. Athira and Dutta, Pritha and Singh, Prashant and Singh, Ashutosh K. and Prasad, Bhagavatula L. V.} } @article {49729, title = {Facet dependence for solvent-modulated proton-coupled electron transfer in furfural acetalization on Pd nanostructures}, journal = {Chemical Engineering Journal}, volume = {514}, year = {2025}, month = {JUN}, pages = {163159}, type = {Article}, abstract = {

Furfural dialkyl acetals prepared via acetalization reaction of furfural and alcohols are promising biofuels. Using defined experiments and density functional theory (DFT) simulations, the structure-dependent activity and selectivity for furfural acetalization reaction in the presence of alcohols (methanol, ethanol, propanol and butanol) as solvents was studied over well-defined supported Pd nanostructures (octahedra (111), cubes (100) and spheres (both (111) and (100)). Pd cubes supported over TiO2 in the presence of ethanol as a solvent (at 303 K and balloon pressure H-2) exhibited 78 \% conversion and 100 \% selectivity for furfural diethyl acetal product in a short time (similar to 180 min). In contrast, Pd octahedra (111) and Pd spheres showed low conversions (18 \% and 6 \%) at the same reaction conditions. Interestingly, when used as a solvent, methanol showed the highest conversion (90 \%) and selectivity (100 \%) for furfural acetalization over Pd cubes. DFT simulations provided mechanistic insight into the reactivity of the two different Pd facets (111) and (100) in the presence of alcohol molecules towards furfural acetalization reaction. A three-step reaction mechanism was proposed for furfural acetalization with alcohols: (i) alcohol hydroxyl-dehydrogenation (ii) hydrogenation of furfural carbonyl oxygen, and (iii) formation of hemiacetal product. For all three steps, Pd (100) exhibited low activation barriers (51.6, 26.7 and 76.2 kJ/mol) compared to Pd (111) surface (78.6, 35.8 and 92.2 kJ/mol) in the presence of ethanol. The activation barriers for the above steps were further reduced to 47.8, 23.9 and 64.6 kJ/mol on Pd (100) in the presence of methanol, explaining the experimental high reactivity aided by methanol. DFT calculations elucidated the role of the hydrogen bonding network between the solvent molecules and adsorbate, enabling proton-coupled electron transfer for accelerated reactions.

}, keywords = {Acetalization, DFT, facet-dependent reactivity, furfural, Furfural dialkyl acetals, solvent effect}, issn = {1385-8947}, doi = {10.1016/j.cej.2025.163159}, author = {Porwal, Govind and Dandekar, Pallavi and Gorai, Twinkle and Khan, Tuhin Suvra and Haider, M. Ali and Gupta, Shelaka and Vinod, C. P.} } @article {49678, title = {In silico designing of electrocatalysts for hydrogen evolution reaction: a focus on titanium metal-based diboride monolayers}, journal = {International Journal of Hydrogen Energy}, volume = {133}, year = {2025}, month = {JUN }, pages = {91-100}, type = {Article}, abstract = {

Enhancing the efficiency of Hydrogen Evolution Reaction (HER) using chemically modified electrocatalytic titanium diboride surfaces with transition metal-based Single Atom Catalysts (SACs) is illustrated using Density Functional Theory (DFT) based methods employing solvent effects. With higher surface concentrations of nonmetal boron rather than titanium metal, these highly conductive, extremely hard, chemically, and thermally stable electrocatalysts are more cost-effective and superior to their MBene analogs. A systematic analysis of these transition metal-based SACs from the 3d, 4d, and 5d groups embedded in TiB2 monolayer for its HER activity reveals the reduction in limiting potential. As the most effective SAC for improved HER, Zn@TiB2 SAC has a limiting potential of 0.08 eV in acidic and 0.21 eV in alkaline media. The higher exchange current density of Zn@TiB2 (5.74 x 10-5 A cm-2), which exceeds most previously reported electrocatalysts, indicates exceptional HER performance. This work shows that transition metal boride electrocatalysts are economically viable for HER and pave a path for experimentalists.

}, keywords = {AIMD, D -band center, DFT, HER, SAC}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2025.04.482}, author = {Shivankar, Bhavana R. and Verma, Tushar Singh and Krishnamurty, Sailaja} } @article {49720, title = {Synthesis, crystal structure, DFT calculation and catalytic activity of a polymer complex of zinc(II) succinate with 2-amino-1,3,4-thiadiazole}, journal = {Journal of Molecular Structure}, volume = {1338}, year = {2025}, month = {AUG}, pages = {142274}, type = {Article}, abstract = {

A polymer complex of zinc(II) succinate with a 2-amino-1,3,4-thiadialole ligand, denoted as [Zn2L2(suc)2]n, was synthesized and characterized by NMR, ESI-MS, FTIR, and FT-Raman spectroscopy, TGA, and X-ray crystallography. The polymer complex crystallizes in the orthorhombic noncentrosymmetric Pna21 space group and features a five-coordinate zinc ion in a distorted spherical square pyramidal geometry. The Hirshfeld surface analysis was carried out to evaluate the intermolecular interactions. Additionally, computational studies were also conducted to assess the stability of the Zn polymer complex and analyze the electron density distribution of the HOMO and LUMO. The catalytic activity of our complex was tested, interestingly, that showed good results for Biginelli reactions with distinct substrate scope in good to high yield at mild reaction conditions.

}, keywords = {DFT, Dihydropyrimidinones, Polymer complex, succinate, Thiadiazole, zinc}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2025.142274}, author = {Nuralieva, Guzal and Alieva, Mushtariy and Torambetov, Batirbay and Leslee, Denzil Britto Christopher and Senthilkumar, Beeran and Kaur, Simranjeet and Dabke, Niteen B. and Vanka, Kumar and Ashurov, Jamshid and Kadirova, Shakhnoza and Gonnade, Rajesh G.} }