A Rotational/Roto-translational Constraint Method for Condensed Matter

TL;DR

This paper introduces a new rotational and roto-translational constraint algorithm for molecular dynamics simulations, enabling selective constraint of molecules and ions to study rotational effects in condensed matter systems.

Contribution

The authors developed a novel constraint algorithm based on Velocity Verlet, integrated into CP2K, allowing long-time MD simulations with selective rotational constraints.

Findings

The algorithm effectively constrains molecules and ions in MD simulations.

Supports long-time molecular dynamics runs with selective constraints.

Facilitates future studies of rotation-related dynamics in condensed matter.

Abstract

In condensed matter physics, particularly in perovskite materials, the rotational motion of molecules and ions is associated with important issues such as ion conduction mechanism. Constrained Molecular Dynamics (MD) simulations offer a means to separate translational, vibrational, and rotational motions, enabling the independent study of their effects. In this study, we introduce a rotational and roto-translational constraint algorithm based on the Velocity Verlet integrator, which has been implemented into a homebrew version of the CP2K package. The MD results show that our program can selectively constrain the molecules and ions in the system and support long-time MD runs. The algorithm can help the future study of important rotation related dynamic problems in condensed matter systems.