Due to its non-crystalline nature, the glassy state has remained one the most
exciting scientific challenges. To study such materials, Molecular Dynamics
(MD) simulations have been extensively used because they provide a direct view
into its microscopic structure. MD is therefore used not only to reproduce real
system properties but also benefits from detailed atomic scale analysis.
Unfortunately, MD shows inherent limitations because of the limited
computational power. For instance, only the simulations of small systems are
currently permitted, which prevents from studying small compositional changes,
although it is well known that they can dramatically alter system properties.
At this stage, it is tempting to follow topological constraint theory, which
aims at describing macroscopic properties of the glass relying only on the
connectivity of individual atoms, thus considering the complicated glass
network as simple mechanical trusses. Thanks to only basic hand calculations,
this theory has been successful in predicting complex composition and
temperature behavior of glass properties, such as the glass forming ability,
the viscosity of the corresponding liquid or the elasticity. The purpose of my
PhD work is to connect these successful approaches based only on the topology
of the underlying low-temperature network with properties that can be obtained
from MD calculations. It should thus allow for an increased applicability of
rigidity theory.
