Metal-metal closed-shell interaction in M2X2 (M = Ag, Cu; X = Cl, Br, I) and related compounds [Ag2Br2](PH3)(3) and [CU2Cl2](PH3)(2): an RHF, MP2 andDFT study

Calculations for compounds (1-6) of models M2X2 (M = Ag, Cu; X = Cl, Br, I) were performed at HF, MP2 and DFT levels with different basis sets. Geomet ry optimisations were then performed, and the results were compared with a statistical summary of X-ray values. Using the same procedure, calculations on the experimental related compounds [Ag2Br2](PH3)(3) and [Cu2Cl2](PH3)(2 ) (7-8) were done and the theoretical Structures were compared with the exp erimental ones. Theoretical studies of the charge density were also conduct ed in order to analyse the structure and the possible bonding nature of the Metal-Metal and Metal-Ligand interaction. No M ... M interaction was found for the experimentally related compounds 7 and 8. (C) 1999 Elsevier Scienc e B.V. All rights reserved.