Why Quantum Mechanics is Necessary for Describing Molecular Properties. We know that all molecules are made of atoms which, in turn, contain nuclei and electrons. As I discuss in this introductory section, the equations that govern the motions of electrons and of nuclei are not the familiar Newton equations
Application of MR2T2 algorithm in statistical mechanics Canonical ensemble: Distribution function: p(rN)=exp(-E(rN)/KT)/Q Q= JdrN exp(-E(rN)/kT) Different states of the Markov chain: In the application of Metropolis algorithm to a simulation of molecular system, the states of the Markov chain correspond to different configurations of the molecular system