How to Determine Glass Transition Temperature of Polymer Electrolytes from Molecular Dynamics Simulations

Molecular dynamics (MD) simulations become increasingly important to study polymer electrolytes, which are a promising solution for solid-state batteries. Nevertheless, a less-known issue is that the effective temperature in MD simulations is different from those used in experiments partly due to the accuracy of underlying molecular force fields. This calls to use the normalized temperature in MD simulations to better connect with experiment and to report the glass transition temperature (Tg) of simulation systems. Here we show how one can determine Tg with a good consensus by delving into the practical intricacies of setting up MD simulations, choosing different methods of annealing simulations and analyzing the results.