https://idr.niser.ac.in/jspui/handle/123456789/19 Mon, 06 Apr 2026 19:30:49 GMT 2026-04-06T19:30:49Z https://idr.niser.ac.in/jspui/handle/123456789/1271 Title: Guanidinate stabilized germanium(II) and tin(II) amide complexes and their catalytic activity for aryl isocyanate cyclization Authors: Barman, Milan Kr; Baishya, Ashim; Peddarao, Thota; Nembenna, Sharanappa Abstract: Two different synthetic routes for the preparation of guanidinate stabilized germanium(II) and tin(II) amide complexes have been established. First, the reaction of one equiv of bulky guanidine ligand either L1H or L2H [L1 = {ArNC (NiPr2)NAr} (Ar = 2,6-Me2–C6H3) and L2 = {Ar′NC (NiPr2) NAr′}(Ar′ = 2,6-iPr2-C6H3)] with two equiv of KN(SiMe3)2 and one equiv of metal dihalide i.e., MCl2{M = Ge(dioxane) and Sn} led to the formation of guanidinate supported germanium(II) amide, i.e., L1GeN(SiMe3)2 (1) and tin amide, i.e., L1SnN(SiMe3)2 (2) and L2SnN(SiMe3)2 (3) complexes, respectively. Second, deprotonation of L1H upon treatment with M[N(SiMe3)2]2 (M = Ge and Sn) in C6D6 at 80 °C for 12 h, afforded the compounds L1MN(SiMe3)2 M = Ge(1) and Sn(2), respectively. X-ray crystal structures of 1 and 2 revealed that both are in monomeric and metal centers in distorted tetrahedral environments with one vertex occupied by a stereo chemically active lone pair of electrons. Furthermore, compounds 1, 2 and 3 were tested for the catalytic activity in the cyclotrimerization of arylisocyanates, which are exhibiting as excellent catalysts. Mon, 01 Dec 2014 00:00:00 GMT https://idr.niser.ac.in/jspui/handle/123456789/1271 2014-12-01T00:00:00Z https://idr.niser.ac.in/jspui/handle/123456789/1270 Title: Search for supersymmetry with razor variables in pp collisions at √s=7TeV Authors: Swain, Sanjay Kumar Abstract: The razor approach to search for 𝑅–parity conserving supersymmetric particles is described in detail. Two analyses are considered: an inclusive search for new heavy particle pairs decaying to final states with at least two jets and missing transverse energy, and a dedicated search for final states with at least one jet originating from a bottom quark. For both the inclusive study and the study requiring a bottom-quark jet, the data are examined in exclusive final states corresponding to all-hadronic, single-lepton, and dilepton events. The study is based on the data set of proton-proton collisions at √𝑠=7  TeV collected with the CMS detector at the LHC in 2011, corresponding to an integrated luminosity of 4.7  fb−1. The study consists of a shape analysis performed in the plane of two kinematic variables, denoted 𝑀𝑅 and 𝑅2, that correspond to the mass and transverse energy flow, respectively, of pair-produced, heavy, new-physics particles. The data are found to be compatible with the background model, defined by studying event simulations and data control samples. Exclusion limits for squark and gluino production are derived in the context of the constrained minimal supersymmetric standard model (CMSSM) and also for simplified-model spectra (SMS). Within the CMSSM parameter space considered, squark and gluino masses up to 1350 GeV are excluded at 95% confidence level, depending on the model parameters. For SMS scenarios, the direct production of pairs of top or bottom squarks is excluded for masses as high as 400 GeV. Mon, 01 Dec 2014 00:00:00 GMT https://idr.niser.ac.in/jspui/handle/123456789/1270 2014-12-01T00:00:00Z https://idr.niser.ac.in/jspui/handle/123456789/1269 Title: STAR Collaboration Authors: Mohanty, Bedangadas Mon, 01 Dec 2014 00:00:00 GMT https://idr.niser.ac.in/jspui/handle/123456789/1269 2014-12-01T00:00:00Z https://idr.niser.ac.in/jspui/handle/123456789/1268 Title: CMS Collaboration Authors: Swain, Sanjay Kumar Mon, 01 Dec 2014 00:00:00 GMT https://idr.niser.ac.in/jspui/handle/123456789/1268 2014-12-01T00:00:00Z