Description of intra-molecular dynamical behavior is usually made in terms
of effective Hamiltonians for different degrees of freedom. In such a way,
rotational, vibrational, rovibrational, etc., dynamical systems arise in a
natural way in the classical limit as corresponding to effective quantum Ha
miltonians. The main idea of this paper is to answer the following general
question: What kind of features of the quantum energy spectra can be predic
ted on the basis of qualitative (symmetry + topology) analysis of correspon
ding classical systems. (C) 2001 Elsevier Science B.V. All rights reserved.