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Updated: Jun 5, 2025
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Potential energy landscape formalism for quantum molecular liquids
Ali Eltareb1,2, Yang Zhou3,4, Gustavo E Lopez5,6
1Department of Physics, Brooklyn College of the City University of New York, Brooklyn, NY, 11210, USA. aeltareb@gradcenter.cuny.edu.
Communications Chemistry
|December 5, 2024
Summary
We extended the potential energy landscape (PEL) formalism to quantum mechanical liquids like water. This approach accurately describes the behavior of liquid and glassy water, including nuclear quantum effects.
Area of Science:
- Statistical Mechanics
- Quantum Mechanics
- Condensed Matter Physics
Background:
- The potential energy landscape (PEL) formalism is crucial for understanding classical liquids and glasses.
- Previous extensions of PEL to quantum systems were limited to simple models.
- Water's unique properties necessitate quantum mechanical treatment.
Purpose of the Study:
- To extend the PEL formalism to liquid/glassy water, incorporating nuclear quantum effects (NQE).
- To investigate the structure and dynamics of quantum water using path-integral molecular dynamics (PIMD).
- To analyze the influence of NQE on water's thermodynamic properties.
Main Methods:
- Path-integral molecular dynamics (PIMD) simulations with the q-TIP4P/F water model.
- Analysis of the potential energy landscape (PEL) for quantum water.
- Calculation of inherent structure vibrational density of states (IS-VDOS) for quantum systems.
Main Results:
- The PEL of quantum water was found to be Gaussian and anharmonic.
- Ring-polymers in PIMD simulations collapsed at the PEL's local minima (inherent structures).
- NQE significantly influence the structural properties of liquid and glassy water across various pressures.
Conclusions:
- The PEL formalism effectively describes molecular liquids and glasses, including quantum systems.
- This work validates the application of PEL to complex systems like water.
- The findings provide a foundation for further studies on quantum liquids and glasses.
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