BONDING IN THE O P(2X1)/CU(110) SYSTEM ANALYZED IN TERMS OF CU-O-CU CHAIN PROPERTIES

We report ab initio calculations on a set of parallel Cu-O-Cu chains as they occur in the missing-row-type reconstructed system of O p(2 x 1)/Cu(110). The full potential linearized augmented plane wave (FLAPW) method is used to solve the relativistically modified Kohn-Sham equations for an array of parallel chains that is treated as a quasi-isolated slab. The present work was stimulated by a similar LCAO (single-chain) calculation of Courths et al. which, however, was fitted to the experiments by adjusting the hopping and overlap integrals. The results turned out to be partly irreconcilable with an ab initio 7-layer slab calculation on the O p(2 x 1)/Cu(110) by Weimert et al. based on the FLAPW method as the present study. Although the fit of the photoemission experiments to the LCAO-chain calculation appeared to be very conclusive, the inherent assumption of a sole O 2p/Cu 3d intrachain interaction can neither be supported by the previous study on the pertinent 7-layer slab nor by the present ab initio chain calculation.