Regensburg 2019 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MM: Fachverband Metall- und Materialphysik
MM 10: Methods in Computational Materials Modelling (methodological aspects, numerics)
MM 10.1: Talk
Monday, April 1, 2019, 15:45–16:00, H45
Accuracy vs. efficiency? Towards ACKS2-based polarization in force fields — •Patrick Gütlein1, Karsten Reuter1, Harald Oberhofer1, and Jochen Blumberger2 — 1Technische Universität München, Germany — 2University College London
Electronic polarization poses a minor energy contribution compared to the formation and arrangement of covalent bonds, yet it crucially influences both geometric and electronic properties of soft condensed matter and molecular crystals. Frequently, effective force field techniques employed to sample the phase space of such systems insufficiently cover the complex dielectric response to external perturbations. Here, the recently proposed atom-condensed Kohn-Sham density functional theory approximated to second order (ACKS2) approach promises to be a computationally undemanding, still accurate electronic polarization extension to conventional force field methods. It rests on an atom-centered basis set expansion of the linear responses of both the electron density and the Kohn-Sham potential.
In order to provide a generally applicable ACKS2 extension to force fields, we develop a new minimalistic basis set representation composed of s- and p-type Gaussian functions. We demonstrate the efficacy of ACKS2 with the new basis set for a range of molecular model systems including anthracene and tetracene, which are relevant building blocks in common organic semiconductors. Screening a range of external electrostatic perpurbations, we find very good agreement with density functional theory references. This marks an important first step to employ ACKS2 as polarization correction in force fields.