Band structure in104Ag

The level structure of¹⁰⁴Ag has been studied through the¹⁰³Rh (α, 3nγ) reaction at E_α=40 and 45 MeV. The principal features of the proposed level scheme are in agreement with those obtained earlier through heavy ion reaction. Two quasiparttcle-plus-rotor model calculation has been performed, and the results are compared with experimental data.     

Gauge theory ofSU(2) Weyl fermion: Is it consistent?

Gauge theory ofSU(2) Weyl fermions was alleged by Witten to be inconsistent due to global anomaly. Evidences of inconsistency were also reported from contradictions between the anomalousU(1) symmetry and the fact that theSU(2) group is free of local anomaly. Here we show how the zero modes of Dirac operator, ignored by the authors of these arguments, play a decisive role and saveSU(2) Weyl fermions from inconsistency in each case. The symmetric chiral current, obtained by adding the Chern-Simons current to the fermionic chiral current, fails to be conserved precisely due to the contributions of zero modes to the ABJ anomaly equation. The Jacobian of the fermion measure under rigid chiralU(1) transformation is, however, guaranteed to be trivial by the Atiyah-Singer index theorem. Finally, a zero mode is the point of bifurcation of eigenvalue trajectory in the homotopy space. In its neighbourhood the hypothesis of adiabaticity made by Witten breaks down due to violent oscillations between levels, which makes his allegation of global anomaly untenable.     

Explicit operator solution to thirring model with U(n) symmetry

Two explicit solutions to the Thirring model with U(n) symmetry are constructed following Klaiber's approach. Products of fields are obtained in terms of those for the free case and scale dimensions of composite operators are computed.     

Dependence of the knock-on electron cross-section on muon energy in high,medium and low Z elements

Using the recent experimental results of various authors the dependence of the knock-on electron cross-section on primary muon energy has been studied in detail. It is found that the knock-on production cross-section increases with primary muon energy upto at least 32 GeV in accordance with Bhabha's theory for energy transfers greater than 15 MeV.     

Study of binuclear copper(II) complexes involving bridging Schiff bases—I

Summary The synthesis of binuclear complexes obtained by the reaction of aromatic diamines with the ternary complexes of copper(II) with bis(2-pyridyl)amine (dpa) as primary ligand and salicylaldehyde or 2-hydroxynaphthaldehyde as secondary ligand have been reported. The complexes have been characterized by elemental analyses, conductance, electronic and i.r. spectral studies. Magnetic measurements indicate antiferromagnetic exchange between two copper(II) centres. E.s.r. spectra exhibit a Ms=2 transition, supporting the antiferromagnetic coupling.     

Growth and morphology of the single crystals of thermoelectric oxide material NaxCoO2

We have grown single crystals of recently discovered thermoelectric oxide material Na_xCoO₂ using NaCl flux. Crystals of sizes upto 1.5 x 1.5 x 1.5 mm³ having different morphological habits were reproducibly grown. The atomic force microscopic studies show that along c‐axis crystals grow via 2D layer‐by‐layer mechanism. The X‐ray diffraction analyses show that grown crystals are rich in Na content as compared to the starting charge indicating that NaCl flux also acts as a source of Na. The resistivity of the crystals exhibited a linear temperature dependence in the region between 30 and 300 K. © 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim     

Synthesis of a novel thiazole based dipeptide chemosensor for Cu(II) in water

A thiazole-based novel dipeptide module has been synthesized, which exhibited selective Cu(II) recognition in water in the presence of other competing divalent transition metal ions at micromolar concentrations. This is the first example of an entirely synthetic peptide based chemosensor for Cu(II).     

Intramolecular ferromagnetic coupling in bis-oxoverdazyl and bis-thioxoverdazyl diradicals with polyacene spacers

We predict the intramolecular exchange coupling constant (J) for 10 different oxo- and thioxo-verdazyl-based hi-spin ground-state diradicals with linear polyacene couplers of varying length using the broken symmetry approach in an unrestricted DFT framework. The magnetic characteristics of these systems are explained using the spin-density distribution, and an analysis is made by “magnetic” orbitals. The nuclear independent chemical shift (NICS) values have been calculated for the diradicals. The average NICS(1) (1 Å above the ring surface) value per benzenoid ring increases as the size of the coupler increases. So-called ΔNICS(1) values [the difference among average NICS(1) per benzenoid ring in the coupler and the NICS(1) of the linear polyacene molecule] are correlated with J values. Bond orders and hyperfine coupling constants have also been evaluated and analyzed for the diradicals.     

Uses of tensor-induced spin–orbit splitting to locate spherical doubly-magic SHE

Using optimized iso-scalar and iso-vector tensor coupling constants in Skyrme Hartree–Fock calculation which reproduces the splitting of spin–orbit partners 1f_7/2–1f_5/2 in ^40,48Ca and ⁵⁶Ni, the evolution of shells in the nuclear chart have been studied through developments in spin–orbit splitting. Signatures for all the magic numbers have been generated without any exception. The procedure when extended to superheavy region indicates the element with Z = 114 and N = 184 to be a doubly-magic spherical nucleus.     

Synthesis of All Enantiomerically Pure Diastereomers of Aprepitant

Syntheses of all eight enantiomerically pure diastereomers of aprepitant and assignment of absolute configuration at newly generated stereocenters by NMR and x-ray crystallographic analysis were achieved.