Knowledge Bank

Variational calculations of rotational-vibrational energy levels are carried out on $H2O,D2O$, and DHO for $J\le 10$ within the framework of the Watson Hamiltonian. The basis functions are products of vibrational functions and symmetric top rotor functions, where the vibrational functions diagonalize the rotationless (J=0) Hamiltonian. Calculations for the vibrational rotational states using different force fields and different equilibrium geometries are compared with experimental observations. The importance of vibrational rotational interactions on the energy levels and wavefunctions is demonstrated.