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Manuscript Title: Cumulative atomic multipole moments and point charge models describing molecular charge distribution.
Authors: A. Sawaryn, W.A. Sokalski
Program title: CAMM
Catalogue identifier: ABFV_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 52(1989)397
Programming language: Fortran.
Computer: VAX 11/750.
Operating system: VMS 4.6.
Word size: 64
Keywords: Molecular, Structure, Atomic multipole moments, Charge distribution, Ab initio.
Classification: 16.1.

Nature of problem:
Decompostion of molecular multipole moments calculated in ab initio LCAO SCF, CISD or MBPT methods into atomic contributions in order to obtain higher resolution data on molecular charge distribution supplementing Mulliken population analysis and considerably improving convergence of multipole expansion in calculation of molecular electrostatic potentials, electric fields, etc.

Solution method:
Molecular multipole moments calculated in ab initio GAUSSIAN-82 or GAUSSIAN-86 programs are decomposed into sets of uncorrelated (CAMM) and and correlated (CCAMM) cumulative atomic multipole moments (up to hexadecapole moment). In addition, all atomic mutlipole moments are analytically decomposed into sets of off-nuclear point charges reproducing simultaneously all atomic and molecular multipole moments up to quadrupole.

The size of the chemical system is restricted by maximum numbers of atoms and basis functions which are dependent on maximum available computer memory.

Running time:
The time to run the CAMM test is 6 sec. Running time is usually a very small fraction of the time needed for SCF or CISD calculations.