Behaviour of a Bucky-ball under Internal and External Pressures

TL;DR

This study investigates the stability and mechanical properties of the C60 molecule under high internal and external pressures using Tersoff and Brenner potentials, estimating critical pressures and analyzing force constants.

Contribution

It provides new estimates of critical pressures for C60 stability and highlights the importance of the Tersoff potential parameter at high pressures.

Findings

Critical internal and external pressures for C60 instability estimated.

Calculated bulk modulus and force constants at various pressures.

Tersoff potential parameter value significantly affects high-pressure results.

Abstract

We study the behaviour of the C60 molecule under very high internal or external pressure using Tersoff as well as Brenner potentials. As a result, we estimate the critical internal and external pressures that lead to its instability. We also calculate stretching force constant and bulk modulus of this molecule at several pressures under which the molecule remains stable. The values of these estimated here at zero pressure agree closely with those obtained in earlier calculations. We also observe that at high pressures, a finite value of parameter of Tersoff potential gives physically acceptable results in contrast to its value zero, which is usually taken for the carbon systems.