The Voronoi Polyhedra as tools for structure
determination in simple disordered systems
J.C. Gil Montoro and J.L.F. Abascal
ABSTRACT
The structure of some simple fluids is analyzed through the Voronoi
tessellation of the configurations generated by computer simulation.
Special emphasis is put on the investigation of disordering, i.e., the
deviation from solid state properties. The models studied include a
simple Lennard-Jones (LJ) liquid, two quenched states obtained from the
liquid, and a system made of non-interacting particles (the ideal gas)
while a state point corresponding to the LJ solid phase is used as
reference. To perform the Voronoi construction, an algorithm specially
suited for disordered systems is presented. The arrangement of
particles has been studied through the geometrical features of their
Voronoi Polyhedra (VP). It is shown that two parameters can give a
description of the VP in such a way that the disordering of the system
is clearly manifested. One is the volume distribution coefficient of
skewness and the other is the shape of the VP as described by the
convex bodies non-sphericity factor. In particular, the clusters
present in a rapidly quenched liquid are easily revealed in this way.
