title: Properties of Lanthanide Hydroxide Molecules Produced in Reactions of Lanthanide Atoms with H2O2and H2+ O2Mixtures: Roles of the +I, +II, +III, and +IV Oxidation States.
abstract: The reactions of laser-ablated lanthanide metal atoms with hydrogen peroxide or hydrogen plus oxygen mixtures have been studied experimentally in a solid argon matrix and theoretically with the ab initio MP2 and CCSD(T) methods. The Ln(OH)3and Ln(OH)2molecules and Ln(OH)2+cations are the major products, and the reactions to form those hydroxides are predicted to be highly exothermic at the CCSD(T) level. Vibronic interactions are hypothesized to contribute to the abnormalities in deuterium shifts for Ln-OH(D) stretching modes for several hydroxides, consistent with CASSCF calculations. Additional new absorptions were assigned as HLnO or LnOH and OLnOH molecules. The tetrahydroxides of Ce, Pr, and Tb have also been observed. These reactive intermediates were identified from their matrix infrared spectra by using D2O2, HD, D2,16,18O2, and18O2isotopic substitution, by matching observed frequencies with values calculated by electronic structure methods, and by following the trends observed in frequencies going through different lanthanide metal hydroxide series across the periodic table. The lanthanides are in the +II oxidation state for Ln(OH)2and are in the +III oxidation state for Ln(OH)3and Ln(OH)2+.
authors.affiliation: Department of Chemistry, Box 400319, University of Virginia , Charlottesville, Virginia 22904-4319 United States.|Chemistry Department, Tongji University , Shanghai 200093, China.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Box 400319, University of Virginia , Charlottesville, Virginia 22904-4319 United States.
authors.forename: Lester
authors.initials: L
authors.lastname: Andrews
authors.affiliation: Chemistry Department, The University of Alabama , Tuscaloosa Alabama 34487-0336, United States.
authors.forename: Zongtang
authors.initials: Z
authors.lastname: Fang
authors.affiliation: Chemistry Department, The University of Alabama , Tuscaloosa Alabama 34487-0336, United States.
authors.forename: K Sahan
authors.initials: KS
authors.lastname: Thanthiriwatte
authors.affiliation: Chemistry Department, The University of Alabama , Tuscaloosa Alabama 34487-0336, United States.
authors.forename: Mingyang
authors.initials: M
authors.lastname: Chen
authors.affiliation: Chemistry Department, The University of Alabama , Tuscaloosa Alabama 34487-0336, United States.
authors.forename: David A
authors.initials: DA
authors.lastname: Dixon