Potential energy surfaces for the insertion of Ta and Ta sup + into H sub 2

Journal Article · Sun Dec 15 04:00:00 EST 1991 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.461188· OSTI ID:6154572

Dai, D G; Cheng, W; Balasubramanian, K ^[1]

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1. Department of Chemistry, Arizona State University, Tempe, Arizona (USA)

We compute the bending potential energy surfaces of 12 electronic states of TaH{sub 2} and TaH{sup +}{sub 2} using the complete active space multiconfiguration self-consistent field (CAS-MCSCF) followed by multireference singles+doubles configuration interaction (MRSDCI) calculations. Spin--orbit effects are also included using the relativistic configuration interaction (RCI) approach. We find that the {sup 4}{ital F} ground state of Ta atom requires a barrier of {similar to}24 kcal/mol for insertion into H{sub 2} while the {sup 5}{ital F} ground state of Ta{sup +} does not insert into H{sub 2}. The low-spin excited states of Ta and Ta{sup +} are considerably more reactive with H{sub 2}. We find three nearly-degenerate bent electronic states of {sup 4}{ital B}{sub 1}, {sup 4}{ital A}{sub 2}, and {sup 4}{ital B}{sub 2} symmetries as the candidates for the ground state of TaH{sub 2}. Likewise {sup 3}{ital B}{sub 1} and {sup 3}{ital A}{sub 1} electronic states of TaH{sup +}{sub 2} are nearly-degenerate candidates for the ground state. The spin--orbit coupling strongly mixes some of these states leading to bond angle changes of up to 10{degree}.

• DOE Contract Number: FG02-86ER13558
• OSTI ID: 6154572
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 95:12; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ANGULAR MOMENTUM
BOND ANGLE
CATIONS
CHARGED PARTICLES
CHEMICAL REACTIONS
CONFIGURATION INTERACTION
COUPLING
ELEMENTS
ENERGY
ENERGY LEVELS
EXCITED STATES
GROUND STATES
HYDRIDES
HYDROGEN
HYDROGEN COMPOUNDS
INTERMEDIATE COUPLING
IONS
L-S COUPLING
METALS
MOLECULAR IONS
MOLECULES
NONMETALS
PARTICLE PROPERTIES
POTENTIAL ENERGY
REFRACTORY METAL COMPOUNDS
SPIN
SYMMETRY
TANTALUM
TANTALUM COMPOUNDS
TANTALUM HYDRIDES
TANTALUM IONS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS