  We study the driving of colloidal molecular crystals over periodic substrates
such as those created with optical traps. The n-merization that occurs in the
colloidal molecular crystal states produces a remarkably rich variety of
distinct dynamical behaviors, including polarization effects within the pinned
phase and the formation of both ordered and disordered sliding phases. Using
computer simulations, we map the dynamic phase diagrams as a function of
substrate strength for dimers and trimers on a triangular substrate, and
correlate features on the phase diagram with transport signatures.
