ANGLE-RESOLVED X-RAY PHOTOELECTRON SPECTROSCOPIC EXPERIMENTS ON THE FULL SERIES OF MOLECULAR [AU-55(PR(3))(12)CL-6] CLUSTERS

Core and valence spectra have been measured in a series of angle-resol ved high-resolution X-ray photoelectron spectroscopic experiments on t he molecular metal cluster compounds [Au-55(PR(3))(12)Cl-6] with R(3) = Ph(2)(C6H4SO3Na-m), (C(6)H(4)Me-p)(3), (C(6)H(4)OMe-p)(3) or Ph(3) w hich represent all such compounds synthesized to date. Only a limited number of samples satisfies the nominal composition. In some of the sa mples the presence of gold particles, larger than the nominal Au-55 cl usters, is observed. Gold monomers bound to P and Cl are shown to be p resent in a number of samples.