# A new program for calculating matrix elements in atomic structure

## Description

Abstract The solution of many problems concerning the electronic structure of atoms requires the evaluation of the matrix elements of the Hamiltonian operator, including the electrostatic interaction. These matrix elements may be expressed as weighted sums of radial integrals. The program we describe in this paper evaluates the coefficients of the Slater integrals and, if these are given, computes all the matrix elements for a given set of configurations. This program has nearly the same purposes as H... Title of program: COEFANG1 Catalogue Id: ACBF_v1_0 Nature of problem To solve some problems concerning the electronic structure of atoms, one needs to evaluate the matrix elements of the Hamiltonian, including the electrostatic interaction, with respect to a basis set of configuration wave functions. These matrix elements may be expressed as weighted sums of radial Slater integrals. For a given set of configurations, the program defines which wave functions must be included in the basis set, computes all the arising coefficients of the radial integrals and, if th ... Versions of this program held in the CPC repository in Mendeley Data ACBF_v1_0; COEFANG1; 10.1016/0010-4655(91)90011-9 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)