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Updated: Jul 17, 2025
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Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
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Nuclear Quantum Dynamics of Three-Dimensional Condensed-Phase Systems by Constant Uncertainty Molecular Dynamics
1Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8577, Japan.
The Journal of Physical Chemistry Letters
|August 31, 2023
Summary
Constant uncertainty molecular dynamics (CUMD) now simulates three-dimensional systems, including nuclear quantum effects (NQEs). This trajectory-based method offers an alternative for modeling condensed-phase systems like water and ice.
Area of Science:
- Computational Chemistry
- Condensed-Phase Physics
- Molecular Dynamics
Background:
- Molecular dynamics (MD) simulations are crucial for understanding condensed-phase systems.
- Including nuclear quantum effects (NQEs) is essential for accurate simulations.
- Existing methods for NQEs can be computationally intensive.
Purpose of the Study:
- To extend Constant Uncertainty Molecular Dynamics (CUMD) to three-dimensional condensed-phase systems.
- To validate the applicability of CUMD for systems with NQEs.
- To provide an alternative simulation approach for NQEs.
Main Methods:
- Extension of CUMD to 3D condensed-phase simulations.
- Application of CUMD to bulk water and ice Ih using the q-TIP4P/F potential.
- Comparison of CUMD results with established path-integral simulations.
Main Results:
- CUMD successfully simulated 3D condensed-phase systems, including water and ice Ih.
- Simulated properties (radial distribution functions, proton momentum distributions, IR spectra) align with previous studies.
- Demonstrated CUMD's capability to incorporate both static and dynamic NQEs.
Conclusions:
- CUMD is a viable and effective method for including NQEs in MD simulations of 3D condensed-phase systems.
- CUMD serves as a valuable alternative to traditional path-integral methods.
- The study validates CUMD for diverse condensed-phase applications.
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