A novel proof of the DFT formula for the interatomic force field of Molecular Dynamics

作者：Morante S; Rossi G C^*

来源：Annals of Physics, 2017, 377: 71-76.

DOI：10.1016/j.aop.2016.12.011

• DFT
• Atomic force field
• Functional Legendre transform

We give a novel and simple proof of the DFT expression for the interatomic force field that drives the motion of atoms in classical Molecular Dynamics, based on the observation that the ground state electronic energy, seen as a functional of the external potential, is the Legendre transform of the Hohenberg-Kohn functional, which in turn is a functional of the electronic density. We show in this way that the so-called Hellmann-Feynman analytical formula, currently used in numerical simulations, actually provides the exact expression of the interatomic force.

• 出版日期2017-2