01786nas a2200157 4500008004100000022001400041245006900055210006800124260012500192300002300317490000800340520114900348100002001497700001801517856009301535 2014 eng d a0021-960600aScaling up the shape: a novel growth pattern of gallium clusters0 aScaling up the shape a novel growth pattern of gallium clusters aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScAUG aArticle No. 0543080 v1413 a

Putative global minima for Ga+N clusters with size ``N'' ranging from 49 to 70 are found by employing the Kohn-Sham formulation of the density functional theory, and their evolution is described and discussed in detail. We have discovered a unique growth pattern in these clusters, all of which are hollow core-shell structures. They evolve with size from one spherical core-shell to the next spherical core-shell structure mediated by prolate geometries, with an increase in overall diameter of the core, as well as the shell, without putting on new layers of atoms. We also present a complete picture of bonding in gallium clusters by critically analyzing the molecular orbitals, the electron localization function, and Bader charges. Bonding in these clusters is a mixture of metallic and covalent type that leans towards covalency, accompanied by marginal charge transfer from the surface to the core. Most molecular orbitals of Ga clusters are non-jellium type. Covalency of bonding is supported by a wide localization window of electron localization function, and joining of its basins along the bonds. (C) 2014 AIP Publishing LLC.

1 aKaware, Vaibhav1 aJoshi, Kavita uhttps://library.ncl.res.in/content/scaling-shape-novel-growth-pattern-gallium-clusters-001655nas a2200193 4500008004100000022001400041245010800055210006900163260000800232490000800240520099200248653000801240653001201248653000801260653002601268100002001294700001801314856012901332 2024 eng d a1093-326300aSingle-atom alloys of Cu(211) with earth-abundant metals for enhanced activity towards CO2 dissociation0 aSingleatom alloys of Cu211 with earthabundant metals for enhance cJAN0 v1263 a

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.

10aCO210aCu(211)10aDFT10aSingle atom catalysts1 aThakkar, Kavita1 aJoshi, Kavita uhttps://library.ncl.res.in/content/single-atom-alloys-cu211-earth-abundant-metals-enhanced-activity-towards-co2-dissociation02676nas a2200229 4500008004100000022001400041245007700055210006900132260000800201300001400209490000700223520189800230653003402128653003002162653001902192653003902211653003302250100001902283700001902302700001802321856010702339 2024 eng d a0360-319900aSolid state hydrogen storage: Decoding the path through machine learning0 aSolid state hydrogen storage Decoding the path through machine l cJAN a1518-15280 v503 a

We present a machine learning (ML) framework HEART (HydrogEn storAge propeRty predicTor) for identifying suitable families of metal alloys for hydrogen storage under ambient conditions. Our framework includes two ML models that predict the hydrogen storage capacity (HYST) and the enthalpy of hydride formation (THOR) of multi-component metal alloys. We demonstrate that a chemically diverse set of features effectively describes the hydrogen storage properties of the alloys. In HYST, we use absorption temperature as a feature which improved H2wt% prediction significantly. For out-of-the-bag samples, HYST predicted H2wt% with R2 score of 0.81 and mean absolute error (MAE) of 0.45 wt% whereas R2 score is 0.89 and MAE is 4.53 kJ/molH2 for THOR. These models are further employed to predict H2wt% and Delta H for similar to 6.4 million multi-component metal alloys. We have identified 6480 compositions with superior storage properties (H2wt% > 2.5 at room temperature and Delta H < 60 kJ/molH2). We have also discussed in detail the interesting trends picked up by these models like temperature dependent variation in the rate of hydrogenation and alloying effect on H2wt% and Delta H in different families of alloys. Importantly certain elements like Al, Si, Sc, Cr, and Mn when mixed in small fractions with hydriding elements like Mg, Ti, V etc. systematically reduce Delta H without significantly compromising the storage capacity. Further upon increasing the number of elements in the alloy i.e from binary to ternary to quaternary, the number of compositions with lower enthalpies also increases. From the 6.4 million compositions, we have reported new alloy families having potential for hydrogen storage at room temperature. Finally, we demonstrate that HEART has the potential to scan vast chemical spaces by narrowing down potential materials for hydrogen storage.

10aEnthalpy of hydride formation10aHydrogen storage capacity10aMetal hydrides10aPredictive machine learning models10aSolid-state hydrogen storage1 aVerma, Ashwini1 aWilson, Nikhil1 aJoshi, Kavita uhttps://library.ncl.res.in/content/solid-state-hydrogen-storage-decoding-path-through-machine-learning01906nas a2200277 4500008004100000022001400041245017200055210006900227260000800296490000700304520082900311653003601140653004501176653002501221653002001246653005401266100003001320700001701350700002801367700002301395700002901418700002601447700001801473700002101491856011601512 2025 eng d a1434-193X00aSequential nitro-michael addition and reductive cyclization cascade reaction for diastereoselective synthesis of multifunctionalized 3,3′-pyrrolidinyl-spirooxindoles0 aSequential nitromichael addition and reductive cyclization casca cFEB0 v283 a

In this investigation, we elucidated, one-pot two stage efficient synthesis of multifuctionalized spiro[oxindole -3,3 `-pyrrolidine]. The methodology proceeds via organocatalyzed nitro-Michael addition reaction between indolylidenecyanoesters and nitroalkanes to formed nitro-Michael adduct which transformed into multifunctionalized 3,3 `-pyrrolidinyl-spirooxindoles by metal catalyzed reductive cyclization cascade. DFT investigations were conducted to elucidate the mechanism underlying the preferential reduction of the nitro group, with subsequent attack on the nitrile and ester groups remain inert throughout the reaction process. The approach is operationally simple, easily scalable, exhibits compatibility with readily accessible starting material and catalysts, thereby emphasizing cost-effectiveness.

10a3 `-pyrrolidinyl spirooxindoles10aDFT study for regioselective cyclization10aDiastereoselective 310aorganocatalysis10aPd/C catalysed partial reductive spirocyclization1 aNichinde, Chandrakant, B.1 aBhati, Meema1 aGirase, Amardipsing, S.1 aPatil, Baliram, R.1 aChaudhari, Suryakant, S.1 aGamidi, Rama, Krishna1 aJoshi, Kavita1 aKinage, Anil, K. uhttps://library.ncl.res.in/content/sequential-nitro-michael-addition-and-reductive-cyclization-cascade-reaction