STRUCTURE OF TRANS-RH(PH3)(2)(CO)X (X=F, CL) USING HARTREE-FOCK MBPT(2) AND DENSITY-FUNCTIONAL THEORY

A study of trans-Rh(PH3)(2)(CO)X (X = F, Cl) using Hartree-Fock/many-b ody perturbation theory and density functional methods is presented. W e report optimized Hartree-Fock and MBPT(2) structures employing effec tive core potentials with double-xi plus polarization basis sets inclu ding f-type functions. Optimized structures using density functional m ethods, including those with gradient-corrected exchange-correlation f unctionals, are also reported. Both ab initio methods yield complexes which have a slightly distorted square-planar structure with moderate bending of the phosphine ligands toward the halide. The predicted stru cture of the chloro complex is compared with experimental data for tra ns-Rh(PPh(3))(2)(CO)Cl.