Quantum-Classical Correspondence via Liouville Dynamics: I. Integrable   Systems and the Chaotic Spectral Decomposition
  A general program to show quantum-classical correspondence for bound conservative integrable and chaotic systems is described. The method is applied to integrable systems and the nature of the approach to the classical limit, the cancellation of essential singularities, is demonstrated. The application to chaotic systems requires an understanding of classical Liouville eigenfunctions and a Liouville spectral decomposition, developed herein. General approaches to the construction of these Liouville eigenfunctions and classical spectral projectors in quantum and classical mechanics are discussed and are employed to construct Liouville eigenfunctions for classically chaotic systems. Correspondence for systems whose classical analogs are chaotic is discussed, based on this decomposition, in the following paper. 
Joshua Wilkie and Paul Brumer (Chemical Physics Theory Group,   Department of Chemistry, University of Toronto)