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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

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Calculation of Atomic Integrals with Exponentialy Correlated Functions

Nechaev Vladimir Vladimirovich, Saratov State University
Ziganshina Olga Dmitrievna, Yuri Gagarin State Technical University of Saratov
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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