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292. ATCOOR2: A Modification of ATCOOR (QCPE 250)
by Morris Bader, Department of Chemistry, Moravian College, Bethlehem, Pennsylvania 18018 ATCOOR computes Cartesian coordinates (right-hand frame) in angstroms for the atoms in any molecule from values of the bond lengths and a minimum set of bond angles and dihedral angles. Three optional subroutines, RELOC1, RELOC2 and RELOC3, allow reorientations of the molecule to facilitate inspection of coordinates. Subroutines DIMENS, BANGLE and DANGLE provide for calculations of designated interatomic distances, bond angles, and dihedral angles, respectively, either to verify the coordinates and assignments of the main program or to obtain additional geometric data. Subroutine DIPOLE computes molecular dipole moment as the vector sum of bond moments. The bond moments are automatically calculated internally from a table of Pauling electronegativities. The program can handle internally the elements carbon, hydrogen, oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, and iodine. Only slight modifications are required to increase this list. The subroutine MOMENT automatically calculates the molecular weight from a table of atomic wieghts of the elements listed above, the moment of inertia tensor, the principal moments of inertia, the center of mass of the system, and points out the rotational geometric configuration of the molecule. ATCOOR2 is written in standard FORTRAN IV and runs on an 8 Kb IBM 1130 in normal precision (7- decimal digit accuracy). FORTRAN IV (IBM 1130) Lines of Code: 651 Recommended Citation: M. Bader, QCPE 11, 292 (1975). |