A Note Concerning l-Type Doubling in Linear Polyatomic Molecules

Abstract
It is shown that certain Coriolis interaction terms in the rotation‐vibration Hamiltonian of a linear polyatomic molecule give second‐order contributions to the energy which remove the degeneracy of levels associated with the quantum number l of internal angular momentum arising from a doubly degenerate perpendicular mode of oscillation. This type of splitting is called ``l‐type doubling'' because it is exactly like ``Λ‐type doubling'' in the electronic energy levels of diatomic molecules.