Dynamics, thermodynamics properties and potential energy landscape of germanium dioxide

We present the results of a molecular dynamics simulations in which we investigate the relationships between the potential energy landscape (PEL), dynamics properties and thermodynamics properties of germanium dioxide (GeO2). Pair distribution functions (PDF) of inherent structure (IS) are calculated and show that the IS have an analogy to amorphous. The dynamics of GeO2 on the PEL is described by distance matrix (DM). This result gives evidence that the glass transition is related to a change in the properties of the PEL explored by the liquid. The connection between the excess entropy and diffusivity is demonstrated. The diffusion coefficient is shown to depend exponentially on the excess entropy. The diffusion coefficient and the excess entropy show a break point at about 3400 K. It is straightforward to evaluate the excess entropy and diffusion coefficient from simulations data, this relation should provide an interrelationship between dynamics and thermodynamics.