# A general program for computing angular integrals of the non-relativistic Hamiltonian with non-orthogonal orbitals

## Description

Abstract The MCHF NONH program performs the angular integrations necessary for expressing the matrix elements of the non-relativistic Hamiltonian as linear combinations of Slater integrals and kinetic integrals. All matrix elements for a given list of configuration states may be evaluated or certain subsets. A limited amount of non-orthogonality between the orbitals may be present leading to overlap integrals in the expressions for the matrix elements. Title of program: MCHF_NONH Catalogue Id: ABZW_v1_0 Nature of problem In configuration interaction calculations as well as variational calculations such as MCHF, the wave function is expanded in terms of a number of configuration state functions. To determine the coefficients in the expansion or the radial functions, as in MCHF, the interaction matrix needs to be expressed in terms of sums of radial integrals. In the presence of non-orthogonal orbitals, the integrals are L- integrals and Slater integrals, possibly multiplied by overlap integrals. The program calcu ... Versions of this program held in the CPC repository in Mendeley Data ABZW_v1_0; MCHF_NONH; 10.1016/0010-4655(91)90136-9 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)