Berlin 2018 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MM: Fachverband Metall- und Materialphysik
MM 67: Methods in Computational Materials Modelling (methodological aspects, numerics)
MM 67.4: Talk
Thursday, March 15, 2018, 18:15–18:30, TC 006
How to simulate nuclear quantum effects accurately at the cost of molecular dynamics — •Venkat Kapil1, Jörg Behler2, Joost VandeVondele3, and Michele Ceriotti1 — 1EPFL, Lausanne, Switzerland — 2Universität Göttingen, Göttingen, Germany — 3CSCS, ETH Zurich, Zurich, Switzerland
The precise description of quantum nuclear fluctuations in atomistic modelling is possible by employing path integral techniques, which involve a considerable computational overhead due to the need of simulating multiple replicas of the system. Consequently, the cost is still prohibitive when combined with advanced electronic structure methods. An elegant way of reducing the number of replicas is by applying a correction based on a high order factorization of the Boltzmann operator. However, the high cost of computing the correction has prevented the use of this technique to condense phase systems. In this work, we present a molecular dynamics scheme which alleviates the cost of explicitly computing the expensive correction, that allows us to utilize the improved efficiency of the high order scheme. Furthermore, we demonstrate how to synergically use multiple time step integration in real and imaginary time to reduce down to zero, the cost of modelling quantum effects while describing inter atomic interactions at high levels of electronic structure theory.