Force Fields

Abstract

For simulation of large system, like a receptor in the lipid bilayer with extra and intracellular water, ab initio and semiempirical methods are, due to the large computing time, not applicable. Therefore, so called force fields are used which map the interaction energies of the system under consideration to simple classical mechanical energy terms. Thus, the most important terms, for calculating the force field energy, are shown. To achieve a further reduction of computational time force fields are based on the site-concept and not on the all atom-concept. The differences between both concepts are explained. Furthermore, based on a simple example—ethanol—the different potential curves are calculated exemplary.