Abstract
Quantum models of rotating-vibrating triatomic molecules are presented. They are specified by model potential functions written in local or collective internal coordinates. For these models the exact rovibrational (RV) wavefunctions and energy levels are calculated for low values of the angular momentum quantum number J. For some states with high J approximate analytic formulae for energy levels are given. The proposed models are realistic and describe correctly the main features of RV states. New physical effects which occur in molecules due to strong rotation-vibration interaction are discussed.