Electron-phonon interaction and superconductivity in hexagonal BaSn5

Abstract

We have made an extensive study of the electronic band structure and phonon spectrum, and the electron-phonon interaction, in BaSn5 by employing an ab initio pseudopotential method and a linear response scheme. The Sn atoms are identified to make a significant contribution to the electronic density of states very close to the Fermi energy and to the average electron-phonon coupling parameter. Using the computed value of 0.96 for the average electron-phonon coupling parameter, we evaluate the superconducting critical temperature and the electronic specific heat coefficient are found to be 4.23 K and 12.9 mJ/molK(2)) respectively, in good accordance with the corresponding experimental values of 4.4 K and 10.8 mJ/(molK(2)).