Finite-volume variational method: First application to direct molecular photoionization

Journal Article · Thu Mar 01 04:00:00 EST 1984 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.29.1214· OSTI ID:7187281

Le Rouzo, H; Raseev, G

A new finite-volume variational method (FVVM) devised for ab initio calculation of molecular continuum wave functions is presented. It is a generalization of Kohn's FVVM which appeared in the same paper (W. Kohn, Phys. Rev. 74, 1763 (1948)) as the well-known principle for phase shifts. In FVVM, the inner-region continuum wave functions are expanded onto a finite basis set. A symmetrization of the Hamiltonian matrix is realized by introducing a set of unknown logarithmic derivatives b at the surface boundary. This leads to a generalized system of eigenequations in terms of the unknowns, namely, the expansion coefficients and eigenvalues b. The proposed method combines the respective advantages of R-matrix and eigenchannel theories in the sense that the system of eigenequations is solved only once and that the eigenfunctions so obtained are uniformly convergent at the surface boundary, where collision information may be extracted by matching. As a model calculation, we use FVVM to calculate eigenphases and cross sections for the photoionization of H/sub 2/ /sup +/(1sigma/sub g/..-->..Esigma/sub u/). Very encouraging results are obtained that demonstrate the numerical feasibility of the method.

• Research Organization: Laboratoire de Photophysique Moleculaire du Centre National de la Recherche Scientifique, Universite ParisSud, Btiment 213, F-91405 Orsay Cedex, France
• OSTI ID: 7187281
• Journal Information: Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 29:3; ISSN PLRAA
• 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
CROSS SECTIONS
ELEMENTS
FUNCTIONS
HAMILTONIANS
HYDROGEN
HYDROGEN IONS
HYDROGEN IONS 2 PLUS
IONIZATION
IONS
MATHEMATICAL OPERATORS
MATRICES
MOLECULAR IONS
NONMETALS
PHOTOIONIZATION
QUANTUM OPERATORS
R MATRIX
VARIATIONAL METHODS
WAVE FUNCTIONS