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Updated: May 18, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Free-energy calculation via mean-force dynamics using a logarithmic energy landscape
Tetsuya Morishita1, Satoru G Itoh, Hisashi Okumura
1Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan. t-morishita@aist.go.jp
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
This study introduces a novel free-energy calculation method using mean-force dynamics. It efficiently samples rare events by enhancing barrier crossing and allows on-the-fly free-energy estimation without postprocessing.
Area of Science:
- Computational Chemistry
- Statistical Mechanics
Background:
- Free-energy calculations are crucial for understanding molecular processes.
- Conventional methods often struggle with efficient sampling of rare events and require extensive postprocessing.
Purpose of the Study:
- To present a new method for free-energy calculation based on mean-force dynamics.
- To improve the efficiency of sampling rare events and enable on-the-fly free-energy estimation.
Main Methods:
- Utilizes a logarithmic form of free energy to enhance barrier crossing on the free-energy landscape.
- Invokes a conserved quantity in mean-force dynamics for real-time free-energy estimation.
- Benchmarks the method against conventional techniques.
Main Results:
- Demonstrates efficient sampling of rare events.
- Enables on-the-fly free-energy profile estimation without postprocessing.
- Shows high efficiency in free-energy calculations for a glycine dipeptide molecule.
Conclusions:
- The presented method offers an efficient approach for free-energy calculations.
- It overcomes limitations of traditional methods by enabling local and on-the-fly estimations.
- The technique shows promise for complex molecular systems and rare event simulations.
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