The non-rigid group for wagging and torsion modes in methvlamine

Abstract

The non-rigid group (NRG) for the wagging and torsion motions in methylamine is deduced in terms of rotation and inversion operations. The group is compared to that of LonguetHiggins for the same molecule expressed in terms of permutations and permutations-inversion. It is seen that the NRG is isomorphic to that of Longuet-Higgins and the C6v symmetry point group. The character table is deduced, as well as the symmetry eigenvectors in terms of products of trigonometric functions. Selection rules for the infrared torsional-wagging transitions are given, and the band profiles of the spectrum discussed.