Vibrational Analysis

Analyzing normal coordinates is very tedious. Users are normally familiar with the internal coordinates of the system they are studying, but not familiar with the Cartesian coordinates. To help characterize the normal coordinates, a very simple analysis is done automatically, and users are strongly encouraged to use this analysis first, and then to look at the normal coordinate eigenvectors.

In the analysis, each pair of bonded atoms is examined to see if there is a large relative motion between them. By bonded is meant   within the van der Waals' distance. If there is such a motion, the indices of the atoms, the relative distance in Ångstroms, and the percentage radial motion are printed. Radial plus tangential motion adds to 100%, but as there are two orthogonal tangential motions and only one radial, the radial component is printed.

Results for the analysis of vibrations in the range i50 to +50 cm-1, although printed, are not described accurately in the vibrational analysis, due to numerical difficulties.