Random occupation of adsorption sites in the C (2×2) structure of CO on Fe{001}

A low-energy electron-diffraction intensity analysis of the Fe{001} c(2×2)-CO structure confirms the results of photoemission studies by other workers suggesting dissociation of the CO molecule. The data are fitted well by a model with random occupation of fourfold symmetrical sites by carbon and oxygen atoms in a c(2×2) configuration, similar to that proposed earlier by Felter and Estrup and by Riwan, Guillot, and Paigne for Mo{001} c(2×2)-CO. © 1978 The American Physical Society.