Diagrammatic perturbation theory: Many-body effects in the X/sup 1/. sigma. /sup +/ states of first-row and second-row diatomic hydrides

Journal Article · Wed Jun 15 00:00:00 EDT 1977 · J. Chem. Phys.; (United States)

OSTI ID:7216449

Wilson, S; Silver, D M

Diagrammatic many-body perturbation theory is employed in a study of the X/sup 1/..sigma../sup +/ states oif first- and second-row diatomic hydrides at their respective equilibrium nuclear separations. All two-, three-, and four-body terms are determined through third-order in the energy within the algebraic approximation (i.e., parameterization of state functions by expansion in a finite basis). Pade approximants to the energy are constructed. From the first-order wavefunction rigorous upper bounds to the expectation value of the electronic energy are obtained from the Rayleigh quotient. Two different zero-order Hamiltonians are used, and the convergence properties of the resulting perturbation expansions are compared. In both schemes three- and four-body terms are significant, having a magnitude that is as much as 24% of the sum of the second- and third-order terms.

• Research Organization: Applied Physics Laboratory, The Johns Hopkins Univbersity, Laural, Maryland 20810
• OSTI ID: 7216449
• Journal Information: J. Chem. Phys.; (United States), Vol. 66:12
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
BORON HYDRIDES
ELECTRONIC STRUCTURE
HYDROFLUORIC ACID
LITHIUM HYDRIDES
ALUMINIUM HYDRIDES
ELECTRON CORRELATION
HYDRIDES
HYDROCHLORIC ACID
MANY-BODY PROBLEM
PERTURBATION THEORY
SODIUM HYDRIDES
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
BORON COMPOUNDS
CORRELATIONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
LITHIUM COMPOUNDS
SODIUM COMPOUNDS
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory