Gaussian functions in Hylleraas-configuration interaction calculations. V. An accurate ab initio H sup + sub 3 potential-energy surface

Journal Article · Sun Apr 15 04:00:00 EDT 1990 · Journal of Chemical Physics; (USA)

DOI:https://doi.org/10.1063/1.457712· OSTI ID:6830073

Frye, D; Preiskorn, A; Lie, G C; Clementi, E ^[1]

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1. IBM Corporation, Data Systems Division, Department 48B/MS 428, Neighborhood Road, Kingston, New York 12401 (USA)

The near-equilibrium potential-energy surface of the {sup 1}{ital A}{sup {prime}}{sub 1} ground state of H{sup +}{sub 3} has been calculated at 69 different points with the Hylleraas-configuration interaction method using 13{ital s}3{ital p}1{ital d} Cartesian Gaussian basis functions. This new surface is found to be substantially lower in absolute energy than all previous surface calculations. The equilibrium energy of the H{sup +}{sub 3} molecule has also been calculated with a larger 13{ital s}5{ital p}3{ital d} basis set. The minimum energy was found to be {ital E}={minus}1.343 827 9 hartrees at an internuclear distance of {ital R}=1.6500 bohrs in the equilateral triangle configuration. This energy is significantly ({gt}70 cm{sup {minus}1}) lower than the previous best published variational calculation and is outside and below the error bars of the latest quantum Monte Carlo calculation. In addition, a medium-sized basis set of 13{ital s}4{ital p}2{ital d} orbitals was used to predict that the equilibrium separation is {ital R}=1.6499 bohrs.

• OSTI ID: 6830073
• Journal Information: Journal of Chemical Physics; (USA), Journal Name: Journal of Chemical Physics; (USA) Vol. 92:8; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
CATIONS
CHARGED PARTICLES
CONFIGURATION INTERACTION
ELECTRONIC STRUCTURE
ENERGY
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
IONS
MOLECULAR IONS
POTENTIAL ENERGY