A modification of the hybrid quantum/classical mean-field or Ehrenfest method is proposed which allows Lis to reproduce the Boltzmann quantum state populations when simulating the vibrational energy transfer between quantum systems and classical thermal baths. The modified Ehrenfest results are shown to be able to simulate the energy fluxes between the solute vibration and the classical solvent in the proper directions, depending on their relative temperatures. (c) 2005 Elsevier B.V. All rights reserved.