Analytic Interatomic Forces in the Random Phase Approximation

Understand

We discuss that in the random phase approximation (RPA) the first derivative of the energy with respect to the Green's function is the self-energy in the GW approximation.

• This relationship allows us to derive compact equations for the RPA interatomic forces.
• We also show that position dependent overlap operators are elegantly incorporated in the present framework.
• The RPA force equations have been implemented in the projector augmented wave formalism, and we present illustrative applications, including ab initio molecular dynamics simulations, the calculation of phonon dispersion relations for diamond and graphite, as well as structural relaxations for water on boron nitride.