Spurious singularities in the generalized Newton variational method

Barnabás Apagyi, P. Lévay, Károly Ladányi

Research output: Contribution to journalArticle

Abstract

The generalized Newton variational method is applied to the static-exchange approximation of the electron-hydrogen-atom scattering. Slater-type basis functions are employed to expand the amplitude density. Spurious singularities are encountered in both scattering processes. The width of the unphysical singularities is broader in the case of singlet scattering. Anomalous poles appear in narrow regions of the scale parameter and are in evident correlation with the zeros of the determinant of the free-particle Green's operator. As a by-product, simple least-squares extension of the generalized Newton variational method is developed in order to avoid spurious singularities and to recognize whether or not the convergence is of secondary nature.

Original languageEnglish
Pages (from-to)7170-7178
Number of pages9
JournalPhysical Review A
Volume44
Issue number11
DOIs
Publication statusPublished - 1991

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newton
scattering
determinants
hydrogen atoms
poles
operators
approximation
electrons

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Atomic and Molecular Physics, and Optics

Cite this

Spurious singularities in the generalized Newton variational method. / Apagyi, Barnabás; Lévay, P.; Ladányi, Károly.

In: Physical Review A, Vol. 44, No. 11, 1991, p. 7170-7178.

Research output: Contribution to journalArticle

Apagyi, Barnabás ; Lévay, P. ; Ladányi, Károly. / Spurious singularities in the generalized Newton variational method. In: Physical Review A. 1991 ; Vol. 44, No. 11. pp. 7170-7178.
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