A MODULAR MOLECULAR-DYNAMICS QUANTUM DYNAMICS PROGRAM FOR NONADIABATIC PROTON TRANSFERS IN SOLUTION

A new program for non-adiabatic mixed quantum dynamics (QD)/molecular dynamics (MD) simulations of a proton transfer is presented. This prog ram consists on GROMOS96 as MD program and an ad hoc program to perfor m the dynamics of one or more quantum particles in a one or three-dime nsional position representation. The quantum particles do not necessar ily have to be protons. Various switches allow the use of different so lutions of problems occurring at many levels of theory: the interactio n of the protons with atoms of their environment, the proper handling of the time dependence of the state and potential of the proton, the r eference points of the quantum coordinate in the classical configurati on, the coherence and exchange between the classical and the quantum m echanical subsystems and the time evolution of the quantum mechanical state under the influence of a known potential. A protonizable water m odel has been developed and tested. (C) 1997 Elsevier Science B.V.