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Dual kinetic balance approach to basis set expansions for the Dirac equation

V. M. Shabaev·I. I. Tupitsyn·V. A. Yerokhin·G. Plunien·G. Soff
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Abstract

A new approach to finite basis sets for the Dirac equation is developed. It solves the problem of spurious states and, as a result, improves the convergence properties of basis set calculations. The efficiency of the method is demonstrated for finite basis sets constructed from B splines by calculating the one-loop self-energy correction for a hydrogenlike ion.

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V. M. Shabaev, I. I. Tupitsyn, V. A. Yerokhin, G. Plunien, G. Soff. 2003-08-22. Dual kinetic balance approach to basis set expansions for the Dirac equation. https://doi.org/10.1103/physrevlett.93.130405

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