Intermolecular Dynamics of Water: Suitability of Reactive Interatomic Potential

Reactive interatomic potentials for water have been developed by researchers based on their ability of bond breaking and formation, which have numerous advantages and applications in different fields. The question that is being addressed in this work is whether these reactive interatomic potentials properly account for the intermolecular dynamics of water that includes both hydrogen bonding as well as librational motions. It should be noted that breaking and reformation of hydrogen bonds occur prior to covalent bond breaking of water molecules (which requires a significant amount of energy), which has numerous applications in absorption as well as solvation problems. Based on correlations with experimental observations, it has been demonstrated that the current forms of the reactive potentials perform poorly in comparison to other well-established empirical interatomic potential models of water, such as TIP4P/2005f, with regard to the intermolecular dynamics of water. Translational and rotational diffusivities, power spectra, and hydrogen-bond lifetime analyses are carried out and compared to available experimental data as well as those obtained from TIP4P/2005f models to arrive at such conclusions.