Molecular-orbital theory of bonding in FeO and chemisorbed oxygen on Fe(100)

Abstract

A high-spin molecular-orbital study is made of ${}_{}{}^7{}_{}{}^{}\Sigma$ FeO and O chemisorbed to Fe(100) in a small-cluster approximation. Bond lengths, force constants, binding energies, and electron energy levels are in promising agreement with experiment. Comparison is made to the low-energy electron diffraction study of Legg, Jona, Jepsen, and Marcus and the uv photoemission work of Brucker and Rhodin. It is suggested that correct theoretical structural determinations depend in a crucial way on occupying one-electron orbitals in the proper spin configuration.