Probing the geometric and electronic structure of rhodium oxide clusters (RhO)n-(n n- ( n=2-4) by anion photoelectron spectroscopy and theoretical calculations

The cluster configurations of (RhO)n- n- (n n = 2-4) have been examined using photoelectron (PE) velocity-map imaging combined with density functional theory calculations. The PE spectra have provided the anion detachment energies (ADEs) information of three ground states, determined to be 2.40, 2.86, and 2.94 eV for n = 2-4, respectively. The geometric structures have been identified by comparing the density of states (DOS) spectra of several low-lying isomers with the PE spectra. The three cluster configurations consist of a Rhn n (n n = 2-4) core with isolated O atoms bonded to the core, exhibiting planar or quasi-planar geometries. The analysis of magnetic moments and spin densities indicated that the most stable three anions have high spin multiplicities of 4, 5, and 4 for n = 2-4, respectively, with the unpaired electrons delocalized on each of the Rh and O atoms.