Intermolecular Interactions of Large Systems: Boron Nitrides, Acenes, and Coronenes

TL;DR

This paper extends the benchmarking of non-covalent interactions to larger systems, analyzing how interaction energies evolve with size for borazine, acenes, and coronenes, revealing new insights into their scalability.

Contribution

The study introduces an expanded benchmark set including borazine, acenes, and coronenes, providing a more comprehensive understanding of non-covalent interactions across different large molecular systems.

Findings

Borazine dimers behave differently from acenes and coronenes.

Parallel displaced acene dimers show similar results to sandwich structures.

Updated estimates for coronene dimer energy are provided.

Abstract

In a recent contribution [Fishman, V.; Lesiuk, M.; Martin, J.M.L.; Boese, A.D., J. Chem. Theory Comput. 2025, 21, 2311-2324], we introduced another angle at benchmarking non-covalent interactions by not just benchmarking interaction energies of different species, but by considering the evolution of interaction energies with increasing system size. Here, we extend the benchmark set to more species, such as electrostatically bound borazine dimers as well as the minima structures of parallel displaced acene and coronene dimers. While the minimum structures of the parallel displaced acene dimers yield similar results to previously published sandwich-structured acenes, the borazine dimers behave vastly different, yielding yet a more complete picture on non-covalent interactions and their scalability. In contrast, the polycyclic aromatic hydrocarbon structures -- coronenes sandwich-stacked and coronenes parallel displaced -- give results consistent with those obtained for both types of the polyacene series, resulting in an updated estimate for the coronene dimer energy.