UV photoelectron spectra and pseudopotential ab initio calculations on trans-dihalobis(triethylphosphine)platinum complexes (halo = chloro, bromo, iodo)

The He I/He I1 excited photoelectron spectra of trans-Pt(PEt3)2X2 complexes (X = Cl, Br, I) are fully assigned with the aid of pseudopotential extended basis set ab initio calculations (including relativistic corrections for the Pt atom) on the whole series studied. Electronic reorganization energies upon ionization were estimated by means of a first-order perturbative treatment, which was revealed to be sufficiently accurate to allow a consistent interpretation of the experimental data. Moreover, the ab initio results provided new and interesting results that help to clarify the bonding scheme and its variation along the halide substituent series.