SAMPLING CONFIGURATIONS IN MONTE-CARLO SIMULATIONS FOR QUANTUM-MECHANICAL STUDIES OF SOLVENT EFFECTS

Discrete models obtained from computer simulation are in increase use to study solvent effects. The approach consists of generating supermol ecular structures for quantum mechanical calculations. The properties of the solute are calculated as an ensemble average over configuration s generated by the simulation. An analysis of the efficiency of the si mulation shows that the number of configurations necessary for the ens emble average can be reduced drastically. As an application to solvato chromism, the calculated spectral shift of the B-1(2u),,,(pi-pi) tran sition of benzene in water is shown to be the same whether it is calcu lated with many but correlated configurations or with just a few uncor related configurations. (C) 1998 John Wiley & Sons, Inc.