Perturbative atomic structure calculations with B-spline basis sets

Journal Article · Sat May 01 04:00:00 EDT 1993 · Bulletin of the American Physical Society

OSTI ID:281209

Bentley, M; Hansen, J E; Landtman, M ^[1]

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1. and others

Applying B-spline methods to perturbative calculations we present results for the {sup 1,3}P{sup o} splitting of 1s{sup 2}2s2p in the Be isoelectronic sequence, including core-valence interactions. Infinite sums over discreet states and integration over continua are both represented via B-spline basis. As is well known, the first-order approximation to the 2s2p term separation is poor. By considering only the splitting, the task of carrying second-order calculations to effective completion is simplified because several allowed classes of excitations make no contribution. The second-order contribution substantially over-corrects, thus we must consider still higher orders. In addition to evaluating third-order contributions, we are investigating the effectiveness of direct diagonalizations of the most important, interactions, thereby including all orders.

• OSTI ID: 281209
• Report Number(s): CONF-9305421--
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 3 Vol. 38; ISSN 0003-0503; ISSN BAPSA6
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BERYLLIUM
CALCULATION METHODS
ELECTRONIC STRUCTURE
ENERGY LEVELS
PERTURBATION THEORY
SPLINE FUNCTIONS