Related Experiment Video
Updated: Dec 20, 2025

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Phase equilibrium of liquid water and hexagonal ice from enhanced sampling molecular dynamics simulations
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Abstract:
We study the phase equilibrium between liquid water and ice Ih modeled by the TIP4P/Ice interatomic potential using enhanced sampling molecular dynamics simulations. Our approach is based on the calculation of ice Ih-liquid free energy differences from simulations that visit reversibly both phases. The reversible interconversion is achieved by introducing a static bias potential as a function of an order parameter. The order parameter was tailored to crystallize the hexagonal diamond structure of oxygen in ice Ih. We analyze the effect of the system size on the ice Ih-liquid free energy differences, and we obtain a melting temperature of 270 K in the thermodynamic limit. This result is in agreement with estimates from thermodynamic integration (272 K) and coexistence simulations (270 K). Since the order parameter does not include information about the coordinates of the protons, the spontaneously formed solid configurations contain proton disorder as expected for ice Ih.
More Related Videos
Related Concept Videos
Phase Transitions: Melting and Freezing
Phase Diagrams
States of Water
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Heating and Cooling Curves
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
Solubility Equilibria: Ionic Product of Water
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...

