  Using collision driven discrete molecular dynamics (DMD), we investigate the
thermodynamics and dynamics of systems of 500 dumbbell molecules interacting by
a purely repulsive ramp-like discretized potential, consisting of $n$ steps of
equal size. We compare the behavior of the two systems, with $n = 18$ and $n =
144$ steps. Each system exhibits both thermodynamic and dynamic anomalies, a
density maximum and the translational and rotational mobilities show anomalous
behavior. Starting with very dense systems and decreasing the density, both
mobilities first increase, reache a maximum, then decrease, reache a minimum,
and finally increase; this behavior is similar to the behavior of SPC/E water.
The regions in the pressure-temperature plane of translational and rotational
mobility anomalies depend strongly on $n$. The product of the translational
diffusion coefficient and the orientational correlation time increases with
temperature, in contrast with the behavior of most liquids.
