Improved Molecular Dynamics Calculations using High-Order Forces in Real Space Density Functional Theory

We present an improved method for calculation of nonlocal contributions to interatomic forces resulting from the real space density functional theory Hamiltonian. Our method utilizes a high order Gaussian integration scheme. We demonstrate the efficacy of our method through molecular dynamics simulations of polyatomic molecules. We show that our method reduces energy drift for each molecule. Additionally, our method improves convergence of dynamic variables including center of mass drift and vibrational frequency.