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Sound Velocities of Generalized Lennard-Jones (n - 6) Fluids Near Freezing
1Reseash and Edicational Centre for Ion, Bauman Moscow State Technical University, 105005 Moscow, Russia.
Molecules (Basel, Switzerland)
|April 3, 2021
Summary
Sound velocities in Lennard-Jones systems are largely unaffected by attractive forces at the liquid-solid phase transition. The steepness of the repulsive term also shows minimal impact on these sound velocities.
Area of Science:
- Condensed Matter Physics
- Thermodynamics
- Materials Science
Background:
- Previous studies calculated sound velocities for Lennard-Jones systems at liquid-solid coexistence.
- These initial findings indicated sound velocities were invariant along coexistence lines.
Purpose of the Study:
- To investigate the influence of attractive and repulsive forces on sound velocities.
- To provide further evidence on the role of system interactions during phase transitions.
Main Methods:
- Analysis of generalized Lennard-Jones (n-6) fluids.
- Systematic variation of the exponent 'n' in the repulsive term (n=12 to 7).
- Calculation of longitudinal and transverse sound velocities.
Main Results:
- Sound velocities at the fluid-solid phase transition are primarily determined by repulsive interactions.
- Attractive forces have a negligible effect on the magnitude of sound velocities.
- Minor trends related to the steepness of the repulsive term were identified.
Conclusions:
- The magnitude of sound velocities at the fluid-solid phase transition is insensitive to attractive forces.
- The steepness of the repulsive potential has a limited impact on sound velocity magnitudes.
- These findings reinforce the understanding of phase transition dynamics in simple models.
Keywords:
Lennard–Jones systemsfluid–solid phase transitiongeneralized (n − 6) Lennard–Jones potentiallongitudinal and transverse collective modessound velocitiesMore Related Videos
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