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DOE OSTI · 3029232

Siegert-pseudostate formulation with B-splines

Tran Tan, Hoang Bao [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000215116052)·Fontes, Christopher John [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000310872964)·Starrett, Charles Edward [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000215828148)
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Abstract

Siegert states (SSs) serve as a useful basis for studying quantum scattering from finite-range potentials. Since they form a discrete instead of continuous set of eigen-solutions, SSs are convenient for performing electronic structure calculations in atoms, molecules, and plasmas. Numerical instabilities may arise, however, in the computation of SSs if the potential vanishes for some extended region, a situation commonly occurring in plasma calculations. Here, in this paper, we identify the cause of these instabilities as the use of non-localized radial basis functions. We thus advocate the use of localized radial basis functions, in particular B-splines, for more robust computations of SSs.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSB-splinesFull-potential treatmentSiegert statesWarm dense plasmas

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Tran Tan, Hoang Bao [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000215116052), Fontes, Christopher John [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000310872964), Starrett, Charles Edward [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000215828148). 2025-03-26. Siegert-pseudostate formulation with B-splines. https://doi.org/10.1016/j.hedp.2025.101191

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