Electronic structure and energetics of LaNi5, α-La2Ni10H and β-La2Ni10H14

The electronic structure and energetics of LaNi5, its hydrogen solution (alpha-La2Ni10H) and its hydride (beta-La2Ni10H14) were investigated by means of the tight-binding linear muffin-tin orbital method within the atomic sphere approximation (TB-LMTO-ASA). Preferred site occupation of the absorbed hydrogen atoms was investigated in terms of the charge density of the interstitial sites and the total energy, both of which indicate that the 6m site in the P6/mmm symmetry is the most preferred. A negative heat of formation of La2Ni10H14 was obtained after optimising the kinetic energy of the electrons outside the atomic spheres and the interstitial sphere radii. (C) 1998 Elsevier Science S.A. All rights reserved.