Feshbach projection operator calculation of the potential energy surfaces and autoionization lifetimes for He(2 /sup 3/S) --H and He(2 /sup 3/S) --H/sub 2/

Journal Article · Tue Feb 15 04:00:00 EST 1977 · J. Chem. Phys.; (United States)

OSTI ID:7325569

Hickman, A P; Isaacson, A D; Miller, W H

A new technique has been developed for calculating potential energy surfaces and widths for autoionizing molecular systems. The method is based on the use of the Feshbach projection operators P and Q, which are defined within the space of configurations generated from a basis set of square-integrable orbitals. Autoionizing states are then obtained by diagonalizing a particular subblock of the finite Hamiltonian constructed by the CI procedure. These states decay because they are only approximate eigenfunctions of the full finite Hamiltonian. Their lifetimes are evaluated using continuum functions which are expanded in the basis orbitals. Such an expansion is shown to be sufficiently accurate. The present technique is compared with the stabilization method and is found to illuminate certain features of that procedure. Potential surfaces V* and widths GAMMA have been calculated for the Penning ionization transitions He(2 /sup 3/S)+H..-->..He+H/sup +/+e/sup -/ and He(2 /sup 3/S)+H/sub 2/..-->..He+H/sub 2//sup +/+e/sup -/. (AIP)

• Research Organization: Department of Chemistry, and Materials and Molecular Research Division, Lawrence Berkeley Laboratory, University of Californa, Berkeley, California 94720
• OSTI ID: 7325569
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 66:4; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
AUTOIONIZATION
CATIONS
CHARGED PARTICLES
COLLISIONS
CRYOGENIC FLUIDS
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
HELIUM
HYDROGEN
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
IONIZATION
IONS
MOLECULE COLLISIONS
NONMETALS
PENNING EFFECT
RARE GASES