Using quantum mechanical forces in Newtonian molecular dynamics
I'm trying to write some "wrapper" software that uses forces calculated from a quantum mechanical potential (ie. Hartree-Fock, DFT, etc.) to evolve a system according to classical Newtonian mechanics (ignoring any periodic boundary conditions, etc.). I believe I have successfully coded the Velocity Verlet integrator, but I can't quite work out how I'm supposed to manipulate the units of Force, being the energy gradient with respect to the nuclear positions. I was wondering whether anyone could help me out with this. I have velocities in Bohr per second, Force in Hartree per Bohr, and mass is in atomic mass units.
Thanks for taking the time to read my question, and double-thanks for any replies! :)