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Updated: Jun 28, 2026
06:37
Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Structural studies of melting on the picosecond time scale
David van der Spoel1, Filipe R N C Maia, Carl Caleman
1Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-75124 Uppsala, Sweden. spoel@xray.bmc.uu.se
Physical Chemistry Chemical Physics : PCCP
|October 31, 2008
Summary
Ultrafast X-ray studies reveal materials melt in picoseconds. New simulations show ice melting takes a few picoseconds, complementing experimental findings on phase transitions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Ultrafast laser-induced melting studies demonstrate picosecond-scale solid-liquid phase transitions.
- Experimental studies on semiconductors like indium antimonide used X-ray diffraction to measure melting times.
- Computer simulations have recently modeled the thermal melting of ice.
Purpose of the Study:
- To provide an overview of experimental and theoretical melting studies.
- To present new simulations of ice-melting, investigating crystal size effects on scattering.
- To predict Bragg peak decay in laser-heated ice using simulations.
Main Methods:
- Experimental studies utilizing picosecond X-ray pulses.
- Computer simulations of laser-induced melting processes.
- Modeling X-ray scattering from simulated melting ice crystals.
Main Results:
- Non-thermal melting in semiconductors occurs within one picosecond.
- Thermal melting of ice is simulated to occur within a few picoseconds.
- Simulations are compatible with experimental spectroscopy, validating their use in studying phase transitions.
Conclusions:
- Simulations are a powerful complement to experimental studies of phase transitions.
- Crystal size affects scattering in simulations of ice melting.
- Predicted Bragg peak decay provides insights into laser-induced melting dynamics.
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