Hindered rotation of adsorbed diatomic molecules

Two models for hindered rotation of a diatomic molecule adsorbed on a plane uniform surface are considered. In the first only the out-of-plane rotation is perturbed, while in the second both in-plane and out-of-plane rotations are hindered. The resulting eigenvalue equations are solved variationally. The eigenvalues and eigenfunctions obtained are discussed, and comparisons are made with earlier studies.