The use of the GEOVAR keyword in combination with a Frequencies run implies that constraints may be applied to the displacements, even if no coordinates are explicitly frozen. If different coordinates are connected to the same variable in the GEOVAR block, only combined displacements of the atoms will be allowed that correspond to a small change in the GEOVAR variable. For this reason, the combination of the GEOVAR and Frequencies keywords is to be handled with extreme caution. If no constraints are intended, it is recommended not to use the GEOVAR keyword, but to use DEFINE instead, or to specify the coordinates explicitly




