Local structure in a supercooled dipolar molecular liquid

Voronoi tessellation in a system composed of dipolar diatomic molecules is performed at a wide range of temperatures, ranging from the liquid to the supercooled state. Several metric and topological properties of the Voronoi polyhedra are evaluated in order to gain some insight into the local structure of the supercooled state. The distribution of volume and of asphericity, as well as the occurrence rate of the most probable polyhedra are obtained. Joint probability distributions between the mobility of molecules and some topological features of their associated polyhedra are also evaluated. No significant correlations with long-time dynamics are encountered in the supercooled state when considering polyhedra properties such as volume and asphericity. • A linear correlation between translational and rotational order parameters is encountered upon cooling. • The diversity of Voronoi polyhedra decreases significantly in the supercooled state. • Distorted icosahedral structures are relevant in the supercooled state, but a more complex picture arises when analyzing short-order. • Long-time dynamics is not significantly correlated with geometric properties of Voronoi polyhedra in a system composed of rigid asymmetric dipolar molecules.