# MATSUP: A program to obtain two-electron repulsion integrals from a sparse file of P supermatrix elements

## Description

Title of program: MATSUP Catalogue Id: AARZ_v1_0 Nature of problem The iterative resolution of the Roothaan equations in the SCF procedure can be carried out either from the file of two-electron repulsion integrals (pq/rs), or from a file of supermatrix elements, as defined as P pq,rs = (pq|rs) -1/4 [ (pr|qs) + (ps|qr)]. iterative cycles are intrinsically faster when carried out from the P supermatrix file. However, the file of two-electron repulsion integrals is requested when the wavefunction is improved beyond the Hartree-Fock approximation, by means of conf ... Versions of this program held in the CPC repository in Mendeley Data AARZ_v1_0; MATSUP; 10.1016/0010-4655(82)90010-8 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)