  We present a new method which combines Car-Parrinello and Born-Oppenheimer
molecular dynamics in order to accelerate density functional theory based
ab-initio simulations. Depending on the system a gain in efficiency of one to
two orders of magnitude has been observed, which allows ab-initio molecular
dynamics of much larger time and length scales than previously thought
feasible. It will be demonstrated that the dynamics is correctly reproduced and
that high accuracy can be maintained throughout for systems ranging from
insulators to semiconductors and even to metals in condensed phases. This
development considerably extends the scope of ab-initio simulations.
