[ARCHIVE/2008] Hartree-Fock-Roothan (F77)

• NAIVE implementation of Hartree-Fock method in GTO base,
• ARCHIVAL code written in 2008,
• pure FORTRAN 77 syntax,
• C++ port is available,
• released as PUBLIC DOMAIN - use for any purpose.

Features:

• NAIVE SCF loop - O(N^4) complexity,
• calculates TOTAL ENERGY and ORBITALS (represented by coefficients in the matrix),
• read molecule GEOMETRY from file,
• GTO BASIS with parameters read from file,
• write RESULT to the output file.

Limitations:

• Only integrals for S orbitals are implemented,
• the total number of electrons in the system MUST BE EVEN (see restricted Hartree-Fock).

Build:

cd src
make

Usage:

• Create input file containing:
  • molecule geometry in cartessian system,
  • basis name to use (basis must be declared within basis.lib file),
  • example h2.inp file is presented below:

GEOM
H   0.0        0.0    0.0
H   0.742724   0.0    0.0
END_GEOM
6-31G

• Run HFR code (please not that, there is NO .inp extension in the command):

$./hfr h2
iter=           1    Etotal=  -1.0742384810132233
iter=           2    Etotal=  -1.1254203943379362       delta=   5.1181913324712891E-002
iter=           3    Etotal=  -1.1266829266059391       delta=   1.2625322680028805E-003
iter=           4    Etotal=  -1.1267113293037336       delta=   2.8402697794582821E-005
iter=           5    Etotal=  -1.1267119595534241       delta=   6.3024969043645740E-007
iter=           6    Etotal=  -1.1267119735099635       delta=   1.3956539479664798E-008

• Orbitals coefficients should be written to the h2.out file:

Etotal=  -1.1267119735099635

--- Funkcje falowe ---
  1.120426    0.326507    0.767506   -0.123166
 -1.347337    0.272471   -0.686424   -1.708117
 -1.120426    0.326507    0.767506    0.123166
  1.347337    0.272471   -0.686424    1.708117