Theoretica chimica acta

, Volume 75, Issue 3, pp 223–232 | Cite as

Rapidly converging threshold value calculations in screened coulomb potential systems: Critical values of the screening parameter for the Yukawa case

  • Metin Demiralp


In this work, the threshold values of the screening parameter for Yukawa potential systems are obtained by means of a basis set constructed from Laguerre type functions. The Laguerre basis set is modified by an appropriately chosen extra function in order to imitate the true behaviour of the solutions at the boundary points. The method used is a variational scheme and the numerical results are accurate to thirty decimal points. A scaling parameter is also inserted into the structure of the basis functions, the optimized values of which accelerate the convergence. The main goal of this paper is to develop a method which enables us to calculate the threshold values of the screening parameter for low-lying states. The method is quite general and can be extended to all systems whose potentials decay exponentially when the radial variable goes to infinity.

Key words

Screened coulomb potentials Yukawa potentials Variational methods Threshold value calculations 


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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • Metin Demiralp
    • 1
  1. 1.Applied Mathematics DepartmentTübitak, Research Institute for Basic SciencesGebze KocaeliTurkey

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