Theoretical Study for the Site Exchange Mechanism of Anionic 5-Coordinate Pt(II) Complexes with Halide, [PtX(hfac)₂]^- (X = Cl, Br, I, hfac = hexafluoroacetylacetonate)

Abstract

DFT calculations of the intra molecular site exchange process in square pyramidal five coordinate complexes, [PtX(hfac)₂]^- (hfac = 1, 1, 1, 5, 5, 5-hexafluoro-2, 4-pentanedionate, X = Cl, Br, I), were performed. The calculation reproduces well the X-ray molecular structures and the trigonal bipyramidal transition state energies of three possible paths, two of which actually seem to function, show that the order of the trans effect of halide ligands is Cl < Br < I, and that of the cis effect is Cl > Br > I, which is in accordance with the experimental results.