Vibration—Rotation Interaction in Symmetric‐Top Molecules and the Splitting between A1 and A2 Levels

摘要: The main purpose of this paper is to reformulate the theory vibration—rotation interaction in symmetric‐top molecules a way which more accessible practicing spectroscopists than current contact transformation formalism. Also it pointed out that many accurately measured l‐type doubling constants can provide information on cubic as well quadratic potential constants. In Sec. I, analytical expressions for splitting between A1 and A2 rovibrational states are derived starting from Wilson—Howard equation. Although result agrees with Grenier—Besson's formula, method derivation new following three points: (1) scheme orders magnitude terms appearing Hamiltonian has been made definite way. (2) Symmetry considerations relations various have fully used derivation. (3) standard perturbation instead transformation. orde...