Quasiclassical dynamics methods from semiclassical approximations

A variety of quasiclassical approximations to quantum dynamical observables and correlation functions are ob-tained from rigorous semiclassical approximations. All expressions involve classical evolution of the probed dynamical variable with trajectory initial conditions sampled from an appropriate phase space density. The features of the derived approximations are illustrated through several model calculations. 2002 Published by Elsevier Science B.V. 1