First-Principles Molecular Dynamics Methods: An Overview

This chapter proposes an overview of computational approaches used nowadays in the field of first-principles simulations to model amorphous and liquid materials. The scope is to bring to the attention of the readership advances and (still existing) limitations in the description of the interactions among atoms which, starting in general from an ordered crystallographic structure, undergo significant modifications in the underlying electronic structure for the disordered phases. These subtle details are difficult to capture by resorting on classical model potentials and call for an accurate description of the quantum mechanical description of the intimate constituent of a glassy compound. The heavy computational workload associated can be nowadays overcome in virtue of the increasing computing power of last-generation high performance computers. Also of paramount importance are advances in algorithms and methods capable of providing the required speed-up in terms of both performances and accuracy.