The vibration-rotation hamiltonian of linear molecules

Abstract

The correct quantum-mechanical form for the vibration-rotation bamiltonian of a linear molecule is derived by an extension of the method of Wilson and Howard. The absence of the third rotational degree of freedom complicates the relations obeyed by the angular momentum components in this hamiltonian. Calculations of energy levels can be simplified by transforming to the ‘isomorphic’ hamiltonian introduced by Hougen. The application of this isomorphic transformation to other operators is illustrated with the dipole moment operator.