Failure of deterministic and stochastic thermostats to control temperature of molecular systems

TL;DR

This paper examines the limitations of deterministic and stochastic thermostats in molecular dynamics, revealing that improvements in ergodicity do not solve the persistent 'hot solvent/cold solute' issue.

Contribution

It demonstrates that existing thermostats enhancing ergodicity fail to address the 'hot solvent/cold solute' problem in binary liquid systems.

Findings

Kinetic moments and Nosé–Hoover methods improve ergodicity.

These methods do not resolve the 'hot solvent/cold solute' problem.

Limitations of current thermostats are highlighted.

Abstract

We investigate the ergodicity and "hot solvent/cold solute" problems in molecular dynamics simulations. While the kinetic moments and the stimulated Nos\'e--Hoover methods improve the ergodicity of a harmonic-oscillator system, both methods exhibit the "hot solvent/cold solute" problem in a binary liquid system. These results show that the devices to improve the ergodicity do not resolve the "hot solvent/cold solute" problem.