On the estimation of anharmonic densities of states of molecules

A simulation method for the estimation of anharmonic densities of states of classical molecular models is described. The method is based on the equilibrium energy distribution established in an uncoupled dimer of the anharmonic molecule and a reference molecule whose density of states is known analytically as a function of energy. Applications to one-dimensional chain molecules and small clusters of atoms joined by Morse bonds indicate that the method is simple and reliable.