Izvestiya of Saratov University.

Physics

ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)

For citation:

Nechaev V. V., Ziganshina O. D., Suchkova N. K. Calculation of Atomic Integrals with Exponentialy Correlated Functions. Izvestiya of Saratov University. Physics , 2012, vol. 12, iss. 1, pp. 18-25. DOI: 10.18500/1817-3020-2012-12-1-18-25

This is an open access article distributed under the terms of Creative Commons Attribution 4.0 International License (CC-BY 4.0).
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Language: 
Russian
Heading: 
Physics
UDC: 
539.182/.184, 519.677
DOI: 
10.18500/1817-3020-2012-12-1-18-25

Calculation of Atomic Integrals with Exponentialy Correlated Functions

Autors: 
Nechaev Vladimir Vladimirovich, Saratov State University
Ziganshina Olga Dmitrievna, Yuri Gagarin State Technical University of Saratov
Suchkova Natalia Konstantinovna, Saratov State University
Abstract: 

A new type of correlation atomic integrals occurring in variation energy calculations of three-particle Coulomb systems is studied. A integrand in them along with an interparticle distance linear term under an exponent additionally contains a quadratic term. It is demonstrated that these integrals are analytically expressed through Faddeeva function of a pure imaginary argument and its derivatives. A stable and fast algorithm for calculation of Faddeeva function derivatives to the twentieth order is developed. The test values of the studied special functions are provided.

Key words: 
atomic integrals
three-particle Coulomb systems
derivatives of Faddeeva function
stable algorithm for calculation
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