Ligand effects and dimer formation in dicoordinated copper(I) complexes

The dimers of dicoordinated Cu(I) complexes of the type [CuXL], where X− = Cl−, Br−, I−, or CN− and L is a neutral ligand such as NH3, PH3, or CNCH3, have been studied by means of ab initio and density functional calculations. The performance of density functional calculations using the hybrid B3LYP method has been compared with MP2 results. Ligand and conformational effects are analyzed for two types of dimers, notably those in which the monomers retain their linear conformation and associate through Cu–Cu contacts and those in which the X ligands act as bridges resulting in tricoordination of each Cu atom and a rhombic Cu2X2 core.