Molecular dynamics without effective potentials via the Car-Parrinello approach

TLDR

Car‑Parrinello molecular‑dynamics is introduced as a method that simulates atomic and molecular motion without predefined potentials, with an extended discussion of the underlying techniques for readers new to the field. The method couples nuclear dynamics to an on‑the‑fly electronic ground state, achieving stable simulations through density‑functional expressions that make the approach computationally tractable.

Abstract

An introduction to the Car-Parrinello molecular-dynamics method is given, written from the viewpoint of a molecular physicist. This scheme makes it possible to simulate atomic and molecular motion in cluster or bulk systems on an energy surface that is determined 'on the fly', by finding an adiabatic electronic state appropriate to the instantaneous nuclear positions. The crucial stability of the method is discussed at length. The development of computationally tractable expressions is considered in detail, using (local) density-functional techniques to describe the electronic energy surface. An extended account of these techniques is given, suitable for those unfamiliar with them.