The Asymmetric Rotor. VII. Extension of the Calculation of Energy Levels

Abstract
Various methods of computing the energy levels of the asymmetric rotor are reviewed for values of high angular momentum which are required in the interpretation of infra‐red and micro‐wave spectra. A table of values of J=11 and 12 is given and over the whole range of asymmetry −1≤κ≤1. Methods of using the Correspondence Principle, Mathieu functions, harmonic oscillator matrices, and power series expansions are discussed, and this survey indicates there is always a region of some degree of asymmetry where the exact value has to be obtained from the rigorous matrix‐mechanical formulation. Methods of obtaining energy values for small intervals in κ from existing tables are also discussed.