Development of Classical Force Fields for Interfaces between Single Molecules and Au

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 126; no. 30; pp. 5031 - 5039
• Main Authors: Arasu, Narendra P., Vázquez, Héctor
• Format: Journal Article
• Language: English
• Published: American Chemical Society 04.08.2022
• Subjects: A: New Tools and Methods in Experiment and Theory
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/acs.jpca.2c02514

Interfaces between metals and organic materials play an essential role in molecular surface science, photovoltaics, or molecular electronics. Modeling the evolution of interface geometry over sufficiently long timescales requires an accurate parameterization of the relevant metal–molecule interactions. Here, we describe a method for calculating interface parameters from reference density functional theory calculations of small metal–molecule complexes. We apply this method to develop a parameter set for a series of metal–molecule–metal junctions. We study the dynamics of short oligophenyls with amine, methyl-sulfide, or direct Au–C links, which are bonded to Au(111) via small adatom structures. Nanosecond classical molecular dynamics simulations using the generated parameter set reveal insight into molecular degrees of freedom not accessible from ab initio molecular dynamics simulations.