Transferability of carbon potentials for novel carbon polymorphs

Journal article

Choosing a suitable potential model to study dynamic processes in novel structures is an ambitious task often relying on chemical intuition. This paper addresses this challenge through a case study of diaphites, diamond-graphite nanocomposites, that are the only naturally occurring crystalline form of carbon featuring both sp3 and sp2 hybridized atoms. Since their synthesis is expensive and difficult to control, molecular dynamics (MD) simulations of their formation would be highly valuable. However, none of the available carbon potentials explicitly includes diaphites in their parameterization. Here, we benchmark several well-established carbon potentials (Tersoff 1989, Tersoff 1994, REBO-II, LCBOP-I, AIREBO, AIREBO-M, GAP-20, ACE) against ab initio MD (AIMD) at the PBE+D2 level of theory. Comparison of structural labeling disqualified Tersoff 1989, Tersoff 1994, REBO-II, AIREBO, and AIREBO-M. To enable long-timescale simulations on systems of a few thousand atoms, an machine-learning (ML)-AIMD model was developed using AIMD acceleration with an on-the-fly Gaussian approximation potential (GAP). ML-AIMD accurately reproduced AIMD results and was therefore used as a benchmark. Extended testing revealed that ACE is the most transferable and computationally efficient potential for MD simulations of diaphites, reproducing the sp2 fraction across all temperatures at a cost at least four times lower than GAP-20. LCBOP-I performed comparably below 2000 K and remains preferable when computational resources are limited. The presented benchmarking framework efficiently identifies the most suitable potentials and provides a general strategy for selecting MD models for novel materials.

Authors: Malinowska-Trzmielak, Z; Grobert, N; Wilson, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: Modelling and Simulation in Materials Science and Engineering
• Volume: 34
• Issue: 2
• Article number: 025004
• Publication date: 2026-02-05
• Acceptance date: 2026-01-27
• DOI: 10.1088/1361-651x/ae3e04
• EISSN: 1361-651X
• ISSN: 0965-0393
• Language: English
• Keywords: AIMD; carbon polymorphs; diaphites; molecular dynamics; potentials; diamond-graphite nanocomposites