  We report Monte Carlo results for the fluid structure of a system of dimeric
particles interacting via a core-softened potential. More specifically, dimers
interact through a repulsive pair potential of inverse-power form, modified in
such a way that the repulsion strength is softened in a given range of
distances. The aim of such a study is to investigate how both the elongation of
the dimers and the softness of the potential affect some features of the model.
Our results show that the dimeric fluid exhibits both density and structural
anomalies even if the interaction is not characterized by two length scales.
Upon increasing the aspect ratio of the dimers, such anomalies are
progressively hindered, with the structural anomaly surviving even after the
disappearance of the density anomaly. These results shed light on the peculiar
behaviour of molecular systems of non-spherical shape, showing how geometrical
and interaction parameters play a fundamental role for the presence of
anomalies.
