Corevalence correlations for atoms with open shells
Abstract
We present an efficient method of inclusion of the corevalence correlations into the configuration interaction (CI) calculations. These correlations take place in the core area where the potential of external electrons is approximately constant. A constant potential does not change the core electron wave functions and Green's functions. Therefore, all operators describing interaction of M valence electrons and NM core electrons [the core part of the HartreeFock Hamiltonian V{sup NM}, the correlation potential {sigma}{sub 1}(r,r{sup '},E), and the screening of interaction between valence electrons by the core electrons {sigma}{sub 2}] may be calculated with all M valence electrons removed. This allows one to avoid subtraction diagrams which make accurate inclusion of the corevalence correlations for M>2 prohibitively complicated. Then the CI Hamiltonian for M valence electrons is calculated using orbitals in complete V{sup N} potential (the mean field produced by all electrons); {sigma}{sub 1}+{sigma}{sub 2} are added to the CI Hamiltonian to account for the corevalence correlations. We calculate {sigma}{sub 1} and {sigma}{sub 2} using manybody perturbation theory in which dominating classes of diagrams are included in all orders. We use neutral Xe I and all positive ions up to Xe VIII as a testing ground. We found that themore »
 Authors:
 School of Physics, University of New South Wales, Sydney 2052 (Australia)
 Publication Date:
 OSTI Identifier:
 20982512
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.052504; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; CATIONS; CORRELATIONS; ELECTRON DENSITY; ELECTRONIC STRUCTURE; ELECTRONS; ENERGY LEVELS; GREEN FUNCTION; HAMILTONIANS; HARTREEFOCK METHOD; INTERACTIONS; LANDE FACTOR; MANYBODY PROBLEM; MEANFIELD THEORY; PERTURBATION THEORY; POTENTIALS; SCREENING; VALENCE; WAVE FUNCTIONS; XENON
Citation Formats
Dzuba, V. A., and Flambaum, V. V. Corevalence correlations for atoms with open shells. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.052504.
Dzuba, V. A., & Flambaum, V. V. Corevalence correlations for atoms with open shells. United States. doi:10.1103/PHYSREVA.75.052504.
Dzuba, V. A., and Flambaum, V. V. Tue .
"Corevalence correlations for atoms with open shells". United States.
doi:10.1103/PHYSREVA.75.052504.
@article{osti_20982512,
title = {Corevalence correlations for atoms with open shells},
author = {Dzuba, V. A. and Flambaum, V. V.},
abstractNote = {We present an efficient method of inclusion of the corevalence correlations into the configuration interaction (CI) calculations. These correlations take place in the core area where the potential of external electrons is approximately constant. A constant potential does not change the core electron wave functions and Green's functions. Therefore, all operators describing interaction of M valence electrons and NM core electrons [the core part of the HartreeFock Hamiltonian V{sup NM}, the correlation potential {sigma}{sub 1}(r,r{sup '},E), and the screening of interaction between valence electrons by the core electrons {sigma}{sub 2}] may be calculated with all M valence electrons removed. This allows one to avoid subtraction diagrams which make accurate inclusion of the corevalence correlations for M>2 prohibitively complicated. Then the CI Hamiltonian for M valence electrons is calculated using orbitals in complete V{sup N} potential (the mean field produced by all electrons); {sigma}{sub 1}+{sigma}{sub 2} are added to the CI Hamiltonian to account for the corevalence correlations. We calculate {sigma}{sub 1} and {sigma}{sub 2} using manybody perturbation theory in which dominating classes of diagrams are included in all orders. We use neutral Xe I and all positive ions up to Xe VIII as a testing ground. We found that the core electron density for all these systems is practically the same. Therefore, we use the same {sigma}{sub 1} and {sigma}{sub 2} to build the CI Hamiltonian in all these systems (M=1,2,3,4,5,6,7,8). Good agreement with experiment for energy levels and Lande factors is demonstrated for all cases from Xe I to Xe VIII.},
doi = {10.1103/PHYSREVA.75.052504},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

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