Presentation Information
[1P41]Fluctuations at the water interface: a comparison between molecular dynamics simulations and continuum membrane theory
*Hikari Kojima1, Takahiro Yamamoto1 (1. Department of Physics, Tokyo University of Science)
The liquid-vapor interface exhibits microscopic fluctuations driven by the thermal motion of molecules. At the same time, the presence of water layers on a graphene and their unique hydrogen bonding network were theoretically confirmed. We aim to quantify the fluctuations at the liquid-vapor interface in bulk water and water monolayer on graphene. Using MD simulations, we analyze the wavenumber-dependent fluctuation spectra and compare them to predictions from continuum membrane theory. Our results show that the fluctuation behavior agrees well with theoretical predictions for 2D membranes at length scales of a few nanometers. In the long-wavelength regime, the bulk water interface exhibits a divergence in fluctuation amplitude, consistent with the instability of a freestanding 2D membrane. In contrast, the fluctuations of the water monolayer on graphene saturate due to van der Waals interactions with the graphene, despite the internal structural instability of the water layer itself.