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Title: Core-valence correlations for atoms with open shells

Abstract

We present an efficient method of inclusion of the core-valence 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 N-M core electrons [the core part of the Hartree-Fock Hamiltonian V{sup N-M}, 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 core-valence 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 core-valence correlations. We calculate {sigma}{sub 1} and {sigma}{sub 2} using many-body 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 » 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.« less

Authors:
;  [1]
  1. 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; HARTREE-FOCK METHOD; INTERACTIONS; LANDE FACTOR; MANY-BODY PROBLEM; MEAN-FIELD THEORY; PERTURBATION THEORY; POTENTIALS; SCREENING; VALENCE; WAVE FUNCTIONS; XENON

Citation Formats

Dzuba, V. A., and Flambaum, V. V. Core-valence correlations for atoms with open shells. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.052504.
Dzuba, V. A., & Flambaum, V. V. Core-valence correlations for atoms with open shells. United States. doi:10.1103/PHYSREVA.75.052504.
Dzuba, V. A., and Flambaum, V. V. Tue . "Core-valence correlations for atoms with open shells". United States. doi:10.1103/PHYSREVA.75.052504.
@article{osti_20982512,
title = {Core-valence correlations for atoms with open shells},
author = {Dzuba, V. A. and Flambaum, V. V.},
abstractNote = {We present an efficient method of inclusion of the core-valence 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 N-M core electrons [the core part of the Hartree-Fock Hamiltonian V{sup N-M}, 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 core-valence 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 core-valence correlations. We calculate {sigma}{sub 1} and {sigma}{sub 2} using many-body 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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  • No abstract prepared.