Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] aajh_v1_0.gz(35 Kbytes)
Manuscript Title: A general program to calculate atomic continuum processes using the NIEM method.
Authors: R.J.W. Henry, S.P. Rountree, E.R. Smith
Program title: NIEM NIES2
Catalogue identifier: AAJH_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 23(1981)233
Programming language: Fortran.
Computer: IBM 3033.
Operating system: JES2.
RAM: 252K words
Word size: 32
Peripherals: disc.
Keywords: Atomic physics, Close-coupling, Scattering, Cross section, Electron, Positron, Atom, Ion, Coupled integro Differential equation, Excitation, Continuum wave function.
Classification: 2.4.

Subprograms used:
Cat Id Title Reference
AAJG_v1_0 NIEM POTC1 CPC 23(1981)233
AAJI_v1_0 NIEM ASYM3 CPC 23(1981)233
ACWN_v1_0 0001 GRN2 CPC 23(1981)233

Nature of problem:
This program reads the direct potentials, the coefficients in the asymptotic expansion of the potentials, exchange coefficients, and correlation potentials stored on a permanent tape or disc file by NIEM POTC1. It solves the set of integro-differential equations by a non- iterative integral equation method from the origin to a radial boundary R1STOP. The program calls GRN2 which calculates the regular and irregular Green's function for the problem.

Solution method:
The continuum orbitals are determined by using a non-iterative integral equation method to propagate separately the numerator and denominator of the reactance function.

Restrictions:
Essentially determined by NIEM POTC1. Dimensions are set for 80 particular solutions. Larger calculations can be made by recompiling with larger dimensions, which should be done consistently with those used in NIEM POTC1. Instructions on COMMENT cards are given to enable the user to increase the dimensions.

Running time:
The test run took 66.6 and 55.2 s on the IBM 3033.