Program fege

This program calculates the fege model exchange potential for use as a local approximatin to the exact exchange potential. The free-electron gas exchange (fege) potential is based on the formulation of S. Hara, [J. Phys. Soc. Japan 22, 710 (1967)] and is an energy dependent local approximation to the exchange interaction.

Input data records

  1. iuang, iugrd, iuanrd, iuden, iufege
  2. ecor
  3. nengv, (engv(i), i = 1, nengv)

Definition of the input variables

iuang
Input unit with angular grid information
iugrd
Input unit with radial grid information
iuanrd
Input unit with information about l cutoff regions
iuden
Input unit with electron density
iufege
Output unit with fege exchange potential
ecor
Offset energy (in atomic units) used to compute the fege exchange potential. This is usually taken to be the ionization potential of the molecule.
nengv
Number of energies to read in and compute
engv(i)
Scattering electron kinetic energy in eV