Recovery of Symmetry of Non-Empiric Force Fields of Cyclic Molecules in Going to Complete Sets of Equivalent Natural Coordinates

The force field of a benzene molecule computed using the quantum-chemical GAMESS package with a set of independent vibrational coordinates in the approximation B3LYP/cc-pVTZ has been transformed to the set of redundant vibrational coordinates including all groups of the equivalent natural coordinates. It has been demonstrated that by the use of the transformed field all the initial frequencies of normal molecular vibrations may be found and the field symmetry may be recovered, with more adequate and clear forms of normal vibrations.