Quantum mechanical models for systems in solution

An overview of modern theories for the modelling of solvent effects on the state and the properties of quantum mechanical molecular systems is presented. The emphasis here is on the models that exploit a continuum description of the solvent and introduce effective Hamiltonians to represent intermolecular interactions. The main theoretical and numerical aspects of these methods, in which mutual interactions between solute and solvent are included, are presented and discussed. As more specialistic feature, we also analyze their extension to the derivative theory, presenting some selected applications such as the search for the best geometry and the evaluation of molecular response properties in solution. In this context some comments on the eventual inclusion of dynamical aspects are also reported.