Potential-energy surfaces for Pt sub 2 +H and Pt+H interactions

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Journal of Chemical Physics; (USA)

DOI:https://doi.org/10.1063/1.458457· OSTI ID:6985581

Balasubramanian, K; Feng, P Y ^[1]

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1. Department of Chemistry, Arizona State University, Tempe, Arizona 85287-1604 (USA)

Potential-energy surfaces for ten electronic states of Pt{sub 2}H as a function of Pt{sub 2}--H distance are constructed using the complete active space multiconfiguration self-consistent field followed by multireference singles plus doubles configuration interactions which included up to 407 000 configurations. In addition, the spin-orbit effects were included through the relativistic configuration-interaction method. The potential-energy curves of low-lying electronic states of PtH and spectroscopic constants of 11 states of PtH are also computed using the same method. The experimental {ital A}{prime}--{ital X}{sub 2} spectroscopic bands of PtH are reassigned to the {sup 2}{Sigma}{sup +}(II)--1/2(I) transition. A tentative reassignment of the observed {ital B}{prime}--{ital X}{sub 1} system is also suggested. The ground state of Pt{sub 2}H is found to be of {ital E}(I) symmetry when spin-orbit effects are incorporated with a bridged structure ({ital R}{sub {ital e}}(Pt--Pt)=2.46 A, {ital R}{sub {ital e}}(Pt--H)=1.684 A). A very low-lying excited state {ital E}(II) ({ital T}{sub {ital e}}=0.14 eV) was found for Pt{sub 2}H. The {ital D}{sub {ital e}}(Pt{sub 2}H)=59 kcal/mol compared to the {ital D}{sub {ital e}}(PtH)=72 kcal/mol, indicating lower stability of the Pt{sub 2}H bridge compared to PtH diatomic. Some of the low-lying electronic states of PtH, especially 3/2 states, exhibit avoided crossings.

• OSTI ID: 6985581
• Journal Information: Journal of Chemical Physics; (USA), Vol. 92:1; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HYDROGEN
CHEMISORPTION
PLATINUM
SORPTIVE PROPERTIES
PLATINUM HYDRIDES
ELECTRONIC STRUCTURE
CONFIGURATION INTERACTION
L-S COUPLING
POTENTIAL ENERGY
SPECTRAL FUNCTIONS
CHEMICAL REACTIONS
COUPLING
ELEMENTS
ENERGY
FUNCTIONS
HYDRIDES
HYDROGEN COMPOUNDS
INTERMEDIATE COUPLING
METALS
NONMETALS
PLATINUM COMPOUNDS
PLATINUM METALS
SEPARATION PROCESSES
SORPTION
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties