New developments in the GDIS simulation package: Integration of VASP and USPEX

Abstract

A popular first principles simulation code, the Vienna Ab initio Simulation Package (VASP), and a crystal structure prediction (CSP) package, the Universal Structure Predictor: Evolutionary Xtallography (USPEX) have been integrated into the GDIS visualization software. The aim of this integration is to provide users with a unique and simple interface through which most of the steps of a typical crystal optimization or prediction work. This involved, for the latter, not only setting up a CSP calculation with complete support for the latest version of USPEX, but also displaying the many structure results by linking each structure geometry and its energy via interactive graphics. For the optimization part, any structure displayed by GDIS can now be the starting point for VASP calculations, with support for its most commonly used parameters. Atomic and electronic structures can be displayed as well as dynamic properties such as total energy, force, volume, and pressure for each ionic step. It is not only possible to start calculations from the GDIS visualization software, using an in-place task manager, but a running calculation can also be followed, allowing a greater control of the simulation process. The GDIS software is available under the GNU public license in its second version.