Work

High Accuracy Many-Body Calculational Approaches for Excitations in Molecules

Year: 2001

Type: article

Abstract: Two state-of-the-art computational approaches: quantum Monte Carlo and GW with exciton effects [GW-BSE (Bethe-Salpeter equation)] are employed to calculate ionization potentials, electron affinities, and first excited singlet and triplet energies for the silane and methane molecules. Results are in excellent agreement between these dramatically different approaches and with available experiment. The optically forbidden triplet excitation in silane is predicted to lie roughly 1 eV higher than previously reported. In the GW-BSE method, we demonstrate that inclusion of off-diagonal matrix elements in the self-energy operator is crucial for an accurate picture.

Source: Physical Review Letters

DOI: 10.1103/physrevlett.86.472

Authors: Jeffrey C. Grossman, Michael Rohlfing, Lubos Mitas, Steven G. Louie, Marvin L. Cohen

Institutions: University of California, Berkeley, University of Münster, University of Illinois Urbana-Champaign, National Center for Supercomputing Applications

Language: English

Topic: Advanced Chemical Physics Studies

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green