Recursion polynomial expansion of the Green`s function with absorbing boundary conditions: Calculations of resonances of HCO by filter diagonalization

Journal Article · Wed Nov 08 04:00:00 EST 1995 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.470217· OSTI ID:124787

Grozdanov, T P; Mandelshtam, V A; Taylor, H S ^[1]

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1. Department of Chemistry, University of Southern California, Los Angeles, California 90089 (United States)

An iterative method for calculating resonance positions and widths is developed. The system Hamiltonian with an asymptotic complex absorbing potential is represented by a large and sparse matrix. A small set of ``good`` basis functions suitable for diagonalizing the Hamiltonian matrix in a given energy window is generated by acting with a polynomial expansion of the imaginary part of the system Green`s function onto a generic initial wave packet. As an application to a realistic three-dimensional system, the calculation of 65 resonances of the nonrotating HCO molecule up to the energy 9000 cm{sup {minus}1} is presented. The method is shown to be rapidly convergent and accurate, especially for narrow resonances. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

• DOE Contract Number: FG03-94ER14458
• OSTI ID: 124787
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 18 Vol. 103; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOUNDARY CONDITIONS
ENERGY LEVELS
FORMYL RADICALS
GREEN FUNCTION
HAMILTONIAN FUNCTION
ITERATIVE METHODS
POLYNOMIALS
QUANTUM MECHANICS
RECURSION RELATIONS
SERIES EXPANSION