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MM: Fachverband Metall- und Materialphysik
MM 67: Methods in Computational Materials Modelling (methodological aspects, numerics)
MM 67.1: Vortrag
Donnerstag, 15. März 2018, 17:30–17:45, TC 006
Linear Scaling first-principles constant pressure molecular dynamics in Conquest — •Zamaan Raza1, Shereif Mujahed2, David Bowler2, and Tsuyoshi Miyazaki1 — 1National Institute for Materials Science (NIMS), Tsukuba, Japan — 2London Centre for Nanotechnology (LCN), University College London, United Kingdom
Density functional theory (DFT) calculations have become commonplace in the characterisation, design and prediction of materials, but conventional implementations scale poorly. Conquest (http://ordern.github.io) is a first principles electronic structure code that can perform DFT calculations that scale linearly with the number for atoms, and is capable of almost ideal parallel efficiency even when using more than 200,000 cores to deal with million-atom systems. Its capabilities include Born-Oppenheimer molecular dynamics (MD) in the micro-canonical and canonical ensembles, and extended-Lagrangian MD which includes electronic degrees of freedom in the equations of motion, solving fundamental problems involving time-reversibility.
Constant pressure MD provides a closer match to experimental and planetary interior conditions than constant volume, and facilitates the modeling of polymorphic phase transitions. Moreover, it is often difficult to choose the correct volume when modeling complex amorphous or biological systems. In this talk, we discuss the implementation of isobaric-isothermal (NPT) molecular dynamics in Conquest, and demonstrate that efficient and robust NPT simulations are now possible for systems containing 10,000+ atoms.