Sims JS. Hylleraas-Configuration Interaction study of the
1S ground state of the negative Li ion.
JOURNAL OF PHYSICS. B, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS : AN INSTITUTE OF PHYSICS JOURNAL 2017;
50:245003. [PMID:
29379225 PMCID:
PMC5785787 DOI:
10.1088/1361-6455/aa961e]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In a previous work Sims and Hagstrom [J. Chem. Phys. 140, 224312 (2014)] reported Hylleraas-Configuration Interaction (Hy-CI) method variational calculations for the neutral atom and positive ion 1S ground states of the beryllium isoelectronic sequence. The Li- ion, nominally the first member of this series, has a decidedly different electronic structure. This paper reports the results of a large, comparable calculation for the Li- ground state to explore how well the Hy-CI method can represent the more diffuse L shell of Li- which is representative of the Be(2sns) excited states as well. The best non-relativistic energy obtained was -7.500 776 596 hartree, indicating that 10 - 20 nh accuracy is attainable in Hy-CI and that convergence of the r12r34 double cusp is fast and that this correlation type can be accurately represented within the Hy-CI model.
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