ABINITIO CALCULATIONS ON MODEL CHAINS

Ab initio calculations on the linear lithium chain, the linear lithium hydride chain and a beryllium hydride polymer have been performed using the crystal orbital method. The influence of an increase of the basis set, an increase in the number of neighbors and an increase of the density of k-points in the Brillouin zone on the calculated equilibrium geometries and band structures has been studied systematically. A proper description of the unit cell and the interaction between neighboring cells turned out to be most important. Energy bands were found to be extremely sensitive to any variation in the basis set applied. © 1978 Springer-Verlag.