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Observation of Single Transits in Supercooled Monatomic Liquids

Duane C. Wallace·Eric D. Chisolm·Brad E. Clements
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Abstract

A transit is the motion of a system from one many-particle potential energy valley to another. We report the observation of transits in molecular dynamics (MD) calculations of supercooled liquid argon and sodium. Each transit is a correlated simultaneous shift in the equilibrium positions of a small local group of particles, as revealed in the fluctuating graphs of the particle coordinates versus time. This is the first reported direct observation of transit motion in a monatomic liquid in thermal equilibrium. We found transits involving 2 to 11 particles, having mean shift in equilibrium position on the order of 0.4 R_1 in argon and 0.25 R_1 in sodium, where R_1 is the nearest neighbor distance. The time it takes for a transit to occur is approximately one mean vibrational period, confirming that transits are fast.

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Duane C. Wallace, Eric D. Chisolm, Brad E. Clements. 2004-09-23. Observation of Single Transits in Supercooled Monatomic Liquids. https://doi.org/10.1103/physreve.64.011205

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