Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 14: Poster Session I

BP 14.8: Poster

Dienstag, 18. März 2025, 10:00–12:30, P3

Parameterization of a dissipative particle dynamics thermostat (DPD) thermostat for coarse-grained molecular dynamics — •Karan Venkatesh, Viktor Klippenstein, and Nico F. A. van der Vegt — Technische Universität Darmstadt

Coarse-grained (CG) simulations represent a viable approach for modelling dynamics on long length and time scales inaccessible with atomistic simulations. In this work, we present a single-site coarse-graining method designed to match the dynamical and structural properties of a molecular liquid (cyclohexane).

We employ a DPD thermostat, in which the pairwise forces are decomposed into parallel and perpendicular components. An iterative optimization scheme is implemented to parameterize the parallel and perpendicular forces, aiming to match the diffusion coefficient and shear viscosity of the system, respectively. In our study, we find that matching the diffusion coefficient also leads to a match in the shear viscosity. However, this correspondence may not always hold, especially when dealing with structurally anisotropic molecules and soft potentials, as commonly encountered in soft matter systems. This approach can be further extended to simulate mixtures of CG molecular liquids, and study penetrant dynamics in CG polymer melts.

References: 1. V. Klippenstein; N F A van der Vegt; J. Chem. Theory Comput. 2023, 19(4), 1099-1110. 2. M. Tripathy; V Klippenstein; N F A van der Vegt; J. Chem. Phys. 2023, 159(9) 3. C. Junghans; M. Praprotnik; K. Kremer; Soft Matter 2008, 4(1), 156-161

Keywords: DPD thermostat; Molecular liquids; Coarse grain; Parameterization; Molecular dynamics