01783nas a2200169   4500008004100000022001400041245006900055210006800124260007100192300001400263490000800277520117600285100002601461700001401487700001901501856009301520       2014                        eng d  a1932-744700aLarge increase in the energy product of Fe3Se4 by Fe-site doping0 aLarge increase in the energy product of Fe3Se4 by Fesite doping  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB  a4016-40220 v1183 a<p>Fe3Se4 possesses a large coercivity at room temperature. At lower temperature, a coercivity value up to 40 kOe has been achieved. However, due to a relatively lower saturation magnetization value, the energy product of this material is not suitable for its use as rare-earth-free hard magnetic material. Although the anisotropy and magnetic structure of Fe3Se4 have been topics of research, there is no attempt to increase the energy product. Here, we report the synthesis of Fe3-xMnxSe4 (x = 0.01-0.2) nanorods. As required for practical applications, after doping, the Curie temperature remains unchanged; however, at optimum (x = 0.03) doping of manganese ions, the magnetization of the host matrix increases significantly from 4.84 to 7.54 emu/g. The corresponding energy product value was found to be increased by more than 130%. At low temperature (10 K) the energy product shows almost a 2 order of magnitude increase (similar to 0.12 MG Oe), which makes it valuable for many low temperature applications. This improvement is a vital step for its use in some of the household applications where a large volume and relatively lower energy product are needed.</p>1 aBishwas, Mousumi, Sen1 aDas, Raja1 aPoddar, Pankaj  uhttps://library.ncl.res.in/content/large-increase-energy-product-fe3se4-fe-site-doping-002333nas a2200217   4500008004100000022001400041245017900055210006900234260007100303300001400374490000700388520144900395100001701844700002601861700002201887700001801909700002601927700001901953700001701972856012601989       2015                        eng d  a0020-166900aConstruction of polynuclear lanthanide (Ln = Dy-III, Tb-III, and Nd-III) cage complexes using pyridine-pyrazole-based ligands: versatile molecular topologies and smm behavior0 aConstruction of polynuclear lanthanide Ln DyIII TbIII and NdIII   a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP  a8197-82060 v543 a<p>Employment of two different pyridyl pyrazolyl-based ligands afforded three octanudear lanthanide(III) (Ln = Dy, Tb) cage compounds and one hexanudear neodymium(III) coordination cage, exhibiting versatile molecular architectures including a butterfly core. Relatively less common semirigid pyridyl pyrazolyl-based asymmetric ligand systems show an interesting trend of forming polynuclear lanthanide cage complexes with different coordination environments around the metal centers. It is noteworthy here that construction of lanthanide complex itself is a challenging task in a ligand system as soft N-donor rich as pyridyl pyrazol. We report herein some lanthanide complexes using ligand containing only one or two O-donors compare to five N-coordinating sites. The resultant multinuclear lanthanide complexes show interesting magnetic and spectroscopic features originating from different spatial arrangements of the metal ions. Alternating current (ac) susceptibility measurements of the two dysprosium complexes display frequency- and temperature-dependent out-of-phase signals in zero and 0.5 T direct current field, a typical characteristic feature of single-molecule magnet (SMM) behavior, indicating different energy reversal barriers due to different molecular topologies. Another aspect of this work is the occurrence of the not-so-common SMM behavior of the terbium complex, further confirmed by ac susceptibility measurement.</p>1 aBala, Sukhen1 aBishwas, Mousumi, Sen1 aPramanik, Bhaskar1 aKhanra, Sumit1 aFromrn, Katharina, M.1 aPoddar, Pankaj1 aMondal, Raju  uhttps://library.ncl.res.in/content/construction-polynuclear-lanthanide-ln-dy-iii-tb-iii-and-nd-iii-cage-complexes-using-002278nas a2200181   4500008004100000022001400041245011300055210006900168260011000237300001400347490000600361520151700367100001601884700002601900700001801926700002201944856013001966       2016                        eng d  a2040-336400aObservation of magnetic anomalies in one-step solvothermally synthesized nickel-cobalt ferrite nanoparticles0 aObservation of magnetic anomalies in onestep solvothermally synt  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN  a5200-52130 v83 a<p>Magnetic anomalies corresponding to the Verwey transition and reorientation of anisotropic vacancies are observed at 151 K and 306 K, respectively, in NiCoFe2O4 nanoparticles (NPs) synthesized by a modified-solvothermal method followed by annealing. Cationic disorder and spherical shape induced non-stoichiometry suppress the Verwey transition in the as-synthesized NPs. On the other hand, reorientation of anisotropic vacancies is quite robust. XRD and electron microscopy investigations confirm a single phase spinel structure and the surface morphology of the as-synthesized NPs changes from spherical to octahedral upon annealing. Rietveld analysis reveals that the Ni2+ ions migrate from tetrahedral (A) to octahedral (B) sites upon annealing. The Mossbauer results show canted spins in both the NPs and the strength of superexchange is stronger in Co-O-Fe than Ni-O-Fe. Magnetic force images show that the as-synthesised NPs are single-domain whereas the annealed NPs are multi-domain octahedral particles. The FMR study reveals that both the NPs have a broad FMR line-width; and resonance properties are consistent with the random anisotropy model. The broad inhomogeneous FMR line-width, observation of the Verwey transition, tuning of the magnetic domain structure as well as the magnetic properties suggest that the NiCoFe2O4 ferrite NPs may be promising for future generation spintronics, magneto-electronics, and ultra-high-density recording media as well as for radar absorbing applications.</p>1 aDatt, Gopal1 aBishwas, Mousumi, Sen1 aRaja, Manivel1 aAbhyankar, A., C.  uhttps://library.ncl.res.in/content/observation-magnetic-anomalies-one-step-solvothermally-synthesized-nickel-cobalt-ferrite-001916nas a2200217   4500008004100000022001400041245008100055210006900136260008100205300001100286490000700297520112200304653001801426653001801444653002401462653002101486653003601507100002601543700001901569856011001588       2016                        eng d  a0022-372700aStudy of magnetic entropy and heat capacity in ferrimagnetic Fe3Se4 nanorods0 aStudy of magnetic entropy and heat capacity in ferrimagnetic Fe3  aTEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcMAY  a1950030 v493 a<p>Change in the magnetic entropy and specific heat capacity in Fe3Se4 nanorods synthesized by a wet-chemical method in a broad temperature (215-340 K) and magnetic field range (0-60 k Oe) was studied. The isothermal magnetic entropy change (Delta S-M) is estimated by an indirect method from the isothermal magnetization curves measured in this temperature range. S-M(max) of -46 x 10(-2) J kg(-1).K-1 was obtained at similar to 317 K when the field was changed from 0 to 60 kOe. The maximum in the isothermal magnetic entropy change (Delta S-M) is observed in close proximity to TC (similar to 323 K), which is linked to the order-disorder transition. The nature of this transition was analyzed by universal curve behavior. The temperature and magnetic field dependence of specific heat capacity was studied and analyzed to estimate the adiabatic temperature change (Delta T-ad). The magnetic entropy change of Fe3Se4 nanoparticles is found to be comparable with similar ferrite and manganite nanoparticle systems and a broad operating temperature window of similar to 30 K was observed around room temperature.</p>10aheat capacity10airon selenide10aMagnetic anisotropy10amagnetic entropy10aorder-disorder phase transition1 aBishwas, Mousumi, Sen1 aPoddar, Pankaj  uhttps://library.ncl.res.in/content/study-magnetic-entropy-and-heat-capacity-ferrimagnetic-fe3se4-nanorods01992nas a2200193   4500008004100000245012700041210006900168260000800237300001600245490000600261520127800267100001701545700001901562700002701581700002601608700001901634700001701653856012801670       2017                        eng d00aLn(8) (Ln = Gd, Ho, Er, Yb) Butterfly core-exhibiting magnetocaloric effect and field-induced SMM behavior for Er analouge0 aLn8 Ln Gd Ho Er Yb Butterfly coreexhibiting magnetocaloric effec  cDEC  a11341-113450 v23 a<p>In this article, we report four pyridyl-pyrazolyl based poly-nuclear cluster complexes with Ln(8) {Ln = [Gd-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(2)(MeOH)(1), [Ho-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](2), [Er-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(MeOH)(H2O)(3), [Yb-8(III)(mu(3)-OH)(4)(L-1)(4)(DEA)(4)Cl-4](DMF)(MeOH)(4) [DEA = Diethanolamine] cores. The impetus for this study was to explore the magnetic behaviour of lanthanide ions which are often ignored or overlooked. X-ray crystal analysis show that these complexes are isostructural and exhibit an interesting butterfly like topology. The semi-rigidity and asymmetric nature of the ligand led to different coordination environment around the metal centres. The lanthanide ions adopt two types of geometry, a bicapped trigonal prism and a distorted square antiprismatic geometry around the metal center. Such dissimilar coordination environments around the lanthanide centre can have profound effects on their magnetic behaviour. Indeed, the magnetic measurements revealed significant magnetocaloric effect for octanuclear gadolinium complex 1 with magnetic entropy change (-Delta S-m ) of 31.4 J kg(-1) K-1 for Delta H = 9 T at T = 3 K whereas Er analogue complex 3 displayed SMM behavior.</p>1 aBala, Sukhen1 aAdhikary, Amit1 aBhattacharya, Sudeshna1 aBishwas, Mousumi, Sen1 aPoddar, Pankaj1 aMondal, Raju  uhttps://library.ncl.res.in/content/ln8-ln-gd-ho-er-yb-butterfly-core-exhibiting-magnetocaloric-effect-and-field-induced-smm02454nas a2200289   4500008004100000022001400041245016700055210006900222260000800291300001200299490000800311520147400319653002701793653001701820653000801837653001601845653001401861653002201875100002001897700002001917700002201937700001701959700001901976700002601995700002102021856012202042       2018                        eng d  a0020-169300aTetranuclear cubane Cu4O4 complexes as prospective anticancer agents: Design, synthesis, structural elucidation, magnetism, computational and cytotoxicity studies0 aTetranuclear cubane Cu4O4 complexes as prospective anticancer ag  cMAR  a121-1320 v4733 aTwo 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.10aCu4O4 cubane complexes10aCytotoxicity10aDFT10aDNA binding10aMagnetism10aNuclease activity1 aUsman, Mohammad1 aArjmand, Farukh1 aKhan, Rais, Ahmad1 aAlsalme, Ali1 aAhmad, Musheer1 aBishwas, Mousumi, Sen1 aTabassum, Sartaj  uhttps://library.ncl.res.in/content/tetranuclear-cubane-cu4o4-complexes-prospective-anticancer-agents-design-synthesis01873nas a2200169   4500008004100000022001400041245014100055210006900196260000800265300001400273490000700287520121800294100002601512700001801538700001901556856012801575       2021                        eng d  a1144-054600aRaman spectroscopy-based sensitive, fast and reversible vapour phase detection of explosives adsorbed on metal-organic frameworks UiO-670 aRaman spectroscopybased sensitive fast and reversible vapour pha  cAPR  a7145-71530 v453 a<p>In this work, we report highly sensitive, selective, rapid, and reversible detection of explosive molecules in the vapour phase, adsorbed on metal-organic frameworks (MOFs) under ambient laboratory conditions. The sensing is based on the quenching of the Raman intensity of a zirconium-based MOF, Zr6O4(OH)(4)(dcppy)(6) (MOF 1, UiO-67-dcppy; dcppy is 2-phenylpyridine-5,4'-dicarboxylate), where 50% of the signal quenches swiftly within similar to 5 s of its exposure to trinitrophenol (TNP) vapours, while 90% of the Raman signal was quenched in 30 s. The high surface area of porous MOFs provides increased adsorption of various nitro analytes. The quenching of Raman peaks resulted from the pi-pi interactions of the analytes with the benzene ring of the MOF. The sensors have also been proven to be reversible and stable by mild heat treatment (80 degrees C for 5 min). These notable results using Raman spectroscopy point to a new and important approach towards explosive sensing using metal-organic frameworks considering their vast versatility. This work emphasizes the importance of a non-invasive and non-destructive technique that can be used to develop handheld vapour phase explosive detectors.</p>1 aBishwas, Mousumi, Sen1 aMalik, Monika1 aPoddar, Pankaj  uhttps://library.ncl.res.in/content/raman-spectroscopy-based-sensitive-fast-and-reversible-vapour-phase-detection-explosives