Simulation study of pressure and temperature dependence of the negative thermal expansion in Zn(CN)$_2$

TL;DR

This study uses molecular dynamics simulations to comprehensively analyze how pressure and temperature influence the negative thermal expansion in Zn(CN)$_2$, revealing complex behaviors and underlying property connections.

Contribution

It introduces a detailed simulation approach that reproduces and explains the pressure and temperature effects on NTE in Zn(CN)$_2$, including exotic behaviors.

Findings

Reproduces negative thermal expansion in Zn(CN)$_2$

Shows reduction of NTE with increased temperature

Demonstrates pressure enhancement and softening effects

Abstract

Pressure and temperature dependence of the negative thermal expansion in Zn(CN)$_2$ is fully investigated using molecular dynamics simulations with a built potential model. The advantage of this study allows us to reproduce all the exotic behaviours of the material, including the negative thermal expansion (NTE), the reduction of NTE with elevated temperature, the pressure enhancement of NTE and the pressure-induced softening. Results of the study provide us detailed data to link the properties in the energy space and the real space, giving us insights to understand the properties and the connections between them.