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

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Calculation of Atomic Integrals with Exponentialy Correlated Functions

Nechaev Vladimir Vladimirovich, Saratov State University
Ziganshina Olga Dmitrievna, Saratov State Technical University named after Yuri Gagarin
Suchkova Natalia Konstantinovna, Saratov State University

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.

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