title: First-principles calculations of elastic and electronic properties of NbB(2) under pressure.
abstract: The structural parameters, elastic constants and electronic structure of NbB(2) under pressure are investigated by using first-principles plane-wave pseudopotential density functional theory within the generalized gradient approximation (GGA). The obtained results are in agreement with the available theoretical data. It is found that the elastic constants and the Debye temperature of NbB(2) increase monotonically and the anisotropies weaken with pressure. The band structure and density of states (DOS) of NbB(2) under pressure are also presented. It is the σ hole that determines the superconductivity in NbB(2), and the features of the σ bands are unchanged after applying pressure except for a shift of position. The density of states (DOS) at the Fermi level decreases with increasing pressure, in conjunction with Bardeen-Cooper-Schrieffer (BCS) theory, which can predict T(c) decreasing with pressure, in agreement with the trend of the theoretical T(c) versus pressure.
authors.affiliation: School of Physical Science and Technology, Sichuan University, Chengdu 610064, People's Republic of China. Laboratory for Shockwave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, People's Republic of China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Li
authors.forename: Guang-Fu
authors.initials: GF
authors.lastname: Ji
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Xiang-Rong
authors.initials: XR
authors.lastname: Chen
authors.forename: Dario
authors.initials: D
authors.lastname: Alfè