Comprehensive theoretical study of the correlation between the energetic and thermal stabilities for the entire set of 1812 C60 isomers

Abstract

The thermal stability of fullerenes plays a fundamental role in their synthesis and in their thermodynamic and kinetic properties. Here, we perform extensive molecular dynamics (MD) simulations using an accurate machine-learning-based Gaussian Approximation Potential (GAP-20) force field to investigate the energetic and thermal properties of the entire set of 1812 C60 isomers. Our MD simulations predict a comprehensive and quantitative correlation between the relative isomerization energy distribution of the C60 isomers and their thermal fragmentation temperatures. We find that the 1812 C60 isomers span over an energetic range of over 400 kcal mol−1, where the majority of isomers (∼85%) lie in the range between 90 and 210 kcal mol−1 above the most stable C60-Ih buckminsterfullerene. Notably, the MD simulations show a clear statistical correlation between the relative energies of the C60 isomers and their fragmentation temperature. The maximum fragmentation temperature is 4800 K for the C60-Ih isomer and 3700 K for the energetically least stable isomer, where nearly 80% of isomers lie in a temperature window of 4000–4500 K. In addition, an Arrhenius-based approach is used to map the timescale gap between simulation and experiment and establish a connection between the MD simulations and fragmentation temperatures.