Comparative classical and ab initio Molecular Dynamics study of molten and glassy germanium dioxide
Abstract
A Molecular Dynamics (MD) study of static and dynamic properties of molten and glassy germanium dioxide is presented. The interactions between the atoms are modelled by the classical pair potential proposed by Oeffner and Elliott (OE) [Oeffner R D and Elliott S R 1998, Phys. Rev. B, 58, 14791]. We compare our results to experiments and previous simulations. In addition, an ab initio method, the so-called Car-Parrinello Molecular Dynamics (CPMD), is applied to check the accuracy of the structural properties, as obtained by the classical MD simulations with the OE potential. As in a similar study for SiO2, the structure predicted by CPMD is only slightly softer than that resulting from the classical MD. In contrast to earlier simulations, both the static structure and dynamic properties are in very good agreement with pertinent experimental data. MD simulations with the OE potential are also used to study the relaxation dynamics. As previously found for SiO2, for high temperatures the dynamics of molten GeO2 is compatible with a description in terms of mode coupling theory.
Cite
@article{arxiv.0804.2654,
title = {Comparative classical and ab initio Molecular Dynamics study of molten and glassy germanium dioxide},
author = {Michael Hawlitzky and Juergen Horbach and Simona Ispas and Matthias Krack and Kurt Binder},
journal= {arXiv preprint arXiv:0804.2654},
year = {2009}
}
Comments
27 pages, 16 figures