Related Experiment Video
Updated: Jun 4, 2026

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Mapping the density anomaly landscape of water via molecular dynamics: pressure effects
Alexis Torres-Carbajal1, Luz Adriana Nicasio-Collazo2
1Ares Materials Inc., Computational Chemistry Department. 840 F Ave. Suite 103, Plano, TX 75074, United States of America.
Abstract:
The density anomaly of liquid water, characterized by a temperature of maximum density (TMD), is a key manifestation of its complex thermodynamic behavior. In this study, molecular dynamics simulations with the transferable intermolecular potential with four points model (TIP4P/2005) are employed to investigate the effect of pressure on this anomaly over a wide range of temperatures (200-350K) and pressures (1-3000bar) in the isothermal-isobaric (NPT) ensemble. Density-temperature profiles of each isobar are analyzed to determine the TMD in order to construct a pressure-dependent map of the anomaly. Structural analysis includes the radial distribution function, coordination number, hydrogen bonding, and the tetrahedral order parameter. These properties exhibit clear trends with increasing pressure, notably a reduction in local tetrahedral order and hydrogen bond stability, which correlate with the progressive suppression of the density anomaly. This work presents a detailed thermodynamic and structural landscape of water under compression, supporting the relevance of local structural changes in the origin of its anomalous behavior. Results provide a reference for future studies of water under extreme conditions.
More Related Videos
11:03An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
10:52Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
Related Concept Videos
Pressure Variation in a Fluid at Rest
When measuring pressure at two different levels within the fluid, the difference in pressure...
Fluid Pressure
According to Pascal's law, a fluid at rest will generate equal pressure in all directions. This pressure is measured as a force per unit area, and its magnitude depends on the fluid's specific weight or...
Density and Archimedes' Principle
Pressure of Fluids
Hydrostatic Pressure Force on a Curved Surface
Distribution of Molecular Speeds