NAME

clag - Lagrangian Program written in C.

DESCRIPTION

The program clag forms the lagrangian matrix from the one and two particle
density matrices and the one and two electron integrals. The lagrangian is
used for MCSCF and CI derivative calculations.

REFERENCES

Lagrangian:

1.

.nr )E 0

A New Dimension to Quantum Chemistry, Y. Yamaguchi, Y. Osamura, J.D. Goddard, H.
F. Schaefer III, Oxford Univ. Press, (1994).

input.dat Input file
FILE71 Transformed one-electron integrals
FILE72 Transformed two-electron integrals
FILE73 One-Particle Density Matrix
FILE74 Two-Particle Density Matrix

FILE75 Lagrangian
output.dat

INPUT FORMAT

The input for this program is read from the file input.dat. The following
keywords are valid:

**PRINT =** *integer*

.nr )E 0

This option determines the verbosity of the output. A value of 0 prints nothing,
a value of 1 prints calculated ci energy and the various components of the ci
energy, a value of 2 prints the one- and two-electron contributions to the MO
lagrangian as well as the MO lagrangian, a value of 3 prints the one-particle
density matrix, and a value of 4 prints the two-particle density matrix. Do
not use print = 4 unless the test case is very small.

**WRITE_CAS_FILES =** *boolean*

.nr )E 0

If TRUE, then write out the following files in canonical form (p>=q, r>=s,
pq>=rs) in Pitzer order: one-electron integrals (file81), two-electron
integrals (file82), one-particle density matrix (file83), two-particle density
matrix (file84), lagrangian (file85). This is temporary and is intended to aid
in linking DETCI with CASSCF.