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I. R. Shein

Publications and source records attributed to I. R. Shein.

59 records · Page 4Linked to original sources
arXiv2002

Band structure of new superconducting AlB_2-like ternary silicides M(Al_{0.5}Si_{0.5})_2 and M(Ga_{0.5}Si_{0.5})_2 (M= Ca, Sr and Ba)

The electronic band structures of the new superconducting (with T_c up to 7.7K) ternary silicides M(A_{0.5}Si_{0.5})_2 (M= Ca, Sr, Ba; A= Al, Ga) in the AlB_2-type structure have been investigated using the full-potential LMTO method. The calculations showed that the trend in transition temperatures doesn't follow the changes in the density d-states at the Fermi level and probably is associated with phonon-mode frequencies.

cond-mat.supr-con↗
arXiv2002

Effect of metal vacancies on the electronic band structure of hexagonal Nb, Zr and Y diborides

Energy band structures of metal-deficient hexagonal diborides M$_{0.75}$B$_2$ (M = Nb, Zr and Y) were calculated using the full-potential LMTO method. The metal vacancies change the density of states near the Fermi level and this effect is quite different for III-V group transition metal diborides. Contradictory data on superconductivity in diborides may be supposed to be connected with nonstoichiometry of samples. Vacancy formation energies are estimated and analyzed.

cond-mat.supr-con↗
arXiv2001

The band structure of hexagonal diborides ZrB2, VB2, NbB2 and TaB2 in comparison with the superconducting MgB2

The band structure and the Fermi surface of hexagonal diborides ZrB2, VB2, NbB2, TaB2 have been studied by the self-consistent full-potential LMTO method and compared with those for the isostructural superconductor MgB2. Factors responsible for the superconducting properties of AlB2-like diborides are analyzed, and the results obtained are compared with previous calculations and available experimental data.

cond-mat.supr-con↗
arXiv2001

Electronic properties and Fermi surfaces MgCNi$_{3}$ and related intermetallics

The band structure of the new perovskite-like superconductor MgCNi$_{3}$ was studied by the self-consistent FP-LMTO method. The superconducting properties of MgCNi$_{3}$ are associated with an intensive peak in the density of Ni3d states near the Fermi level. The absence of superconductivity for nonstoichiometric compositions MgC$_{1-x}$Ni$_{3}$ is due to the transition of the system to the magnetic state. The possibility of superconductivity was discussed for intermetallics ScBNi$_{3}$, InBNi$_{3}$, MgCCo$_{3}$ and MgCCu$_{3}$ which are isostructural with MgCNi$_{3}$.

cond-mat.supr-con↗