# A program for deriving recoupling coefficients formulae

## Description

Abstract The program we describe in this paper derives the formulae needed to evaluate the recoupling coefficients which arise in the calculation of matrix elements by the methods of Racach algebra, using the graphical techniques introduced by Jucys et al. and El-Baz et al.. The recoupling coefficients are represented by diagrams, which are stored in the computer memory in the form of arrays. These diagrams are transformed according to given rules, so that any diagram may be decomposed into a product ... Title of program: RECOUP Catalogue Id: ABZR_v1_0 Nature of problem In atomic calculations one needs to evaluate the matrix elements of the Hamiltonian operator with respect to a basis set of configuration wave functions. This program derives the formulae needed to evaluate the recoupling coefficients which arise in the calculation of matrix elements by the methods of Racach algebra. Versions of this program held in the CPC repository in Mendeley Data ABZR_v1_0; RECOUP; 10.1016/0010-4655(91)90010-I This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)