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[Licence| Download | New Version Template] acqs_v1_0.gz(9 Kbytes)
Manuscript Title: A program to generate numerical orbital functions.
Authors: W.D. Robb
Catalogue identifier: ACQS_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 1(1970)457
Programming language: Fortran.
Computer: CDC 6600.
Operating system: SCOPE.
RAM: 16K words
Word size: 60
Keywords: Atomic physics, Continuum, Yukawa, De vogelaere, Low energy, Bound, Static, R-matrix, Scattering, Basic functions, Bessel functions, Square well, Eigenfunctions, Wave function.
Classification: 2.7.

Other versions:
Cat Id Title Reference

Nature of problem:
The program BASFUN solves the radial Schrodinger equation for any specified central potential and angular momentum, either at a given energy, or subject to a given R-matrix boundary condition. In both cases the solution can be made orthogonal to any number of specified functions. The eigenfunctions which are obtained in numerical form are required: (a) as continuum basis functions in an R-matrix calculation, (b) as Sturmian functions to be used in the calculation of atomic properties such as the van der Waals coefficient.

Solution method:
The differential equation is integrated using de Vogelaere's method, over intervals specified by the user. The eigenfunction and eigenvalue are found using Newton's iteration method, and orthogonality to the specified functions using the method of Lagrange undetermined multipliers and Simpson's rule.

The dimensions of the storage arrays give a restriction which may be changed by the user. The potential is restricted to a central spin- independent form.

Running time:
This depends on the number of functions to which the solution is orthogonalised, on the number of integration points used and on whether or not an eigensolution is required. The mill time for the test run on the CDC 6600 is 1.1 seconds.