Prediction of the infrared spectrum of water on graphene substrate using hybrid classical/quantum simulation

IR spectroscopy is one of the most important methods for clarifying the microscopic behavior of surficial water. We theoretically predict the IR spectrum of water molecules on a graphene substrate using a hybrid method that combines classical molecular dynamics and density functional theory. The IR spectrum of surficial water is characterized by a blue shift of the stretching mode compared to the spectrum of bulk water, and by the appearance of a small sub-peak at around 2950 cm−1. These changes are related to differences in the OH bond length and bonding pattern for hydrogen bonds.