Guided ion beam and theoretical study of the reactions of Os{sup +} with H{sub 2}, D{sub 2}, and HD

Journal Article · Wed Dec 21 04:00:00 EST 2011 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3669425· OSTI ID:22038807

Hinton, Christopher S; Citir, Murat; Armentrout, P B ^[1]

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1. Department of Chemistry, University of Utah, 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112 (United States)

Reactions of the third-row transition metal cation Os{sup +} with H{sub 2}, D{sub 2}, and HD to form OsH{sup +} (OsD{sup +}) were studied using a guided ion beam tandem mass spectrometer. A flow tube ion source produces Os{sup +} in its {sup 6}D (6s{sup 1}5d{sup 6}) electronic ground state level. Corresponding state-specific reaction cross sections are obtained. The kinetic energy dependences of the cross sections for the endothermic formation of OsH{sup +} and OsD{sup +} are analyzed to give a 0 K bond dissociation energy of D{sub 0}(Os{sup +}-H) = 2.45 {+-} 0.10 eV. Quantum chemical calculations are performed here at several levels of theory, with B3LYP approaches generally overestimating the experimental bond energy whereas results obtained using BHLYP and CCSD(T), coupled-cluster with single, double, and perturbative triple excitations, levels show good agreement. Theory also provides the electronic structures of these species and the potential energy surfaces for reaction. Results from the reactions with HD provide insight into the reaction mechanism and indicate that Os{sup +} reacts via a direct reaction. We also compare this third-row transition metal system with the first-row and second-row congeners, Fe{sup +} and Ru{sup +}, and find that Os{sup +} reacts more efficiently with dihydrogen, forming a stronger M{sup +}-H bond. These differences can be attributed to the lanthanide contraction and relativistic effects.

• OSTI ID: 22038807
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 23 Vol. 135; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
74 ATOMIC AND MOLECULAR PHYSICS
BINDING ENERGY
CROSS SECTIONS
DENSITY FUNCTIONAL METHOD
DEUTERIUM
DIRECT REACTIONS
DISSOCIATION ENERGY
GROUND STATES
HYDROGEN
ION BEAMS
KINETIC ENERGY
MASS SPECTROMETERS
OSMIUM
OSMIUM IONS
POTENTIAL ENERGY
RARE EARTHS
RELATIVISTIC RANGE