Molecular Orbital Calculations of Cu-Halides

An ab initio HF MO theory is applied to CuX, CuX2 (X = F and Cl) and (CuCl)3. Although the detailed sequence of energy levels depends upon the basis set used, high-lying orbital energy levels have largely halogen p-like character, whereas low-lying orbital energy levels have largely Cu 3 d-like character. This is in agreement with the chemical intuition of a highly ionic character of these compounds.