Transient Structured Fluctuations in a 2D Liquid*

Using the Aperture Cross Correlation Function as diagnostic, we find the existence of transient structured fluctuations in the liquid phase of a two-dimensional system with a repulsive, core-softened pair potential [1]. This system supports several hexagonal solid phases, a square solid phase, liquid and hexatic phases, and a quasi-crystalline phase with 12-fold symmetry. Our computer simulations suggest the surprising results that deep within the liquid region and approaching transition boundaries, the structured fluctuations favor only the same symmetries supported in the ordered phases of the system, i.e. three-fold, four-fold, and twelve-fold. To our knowledge, no theory to date suggests why such a system would not display local fluctuations of other symmetries well within the liquid phase.

[1] Z. Krebs, A. B. Roitman, L. M. Nowack, C. Liepold, Binhua Lin, and S. A. Rice, J. Chem. Phys, 149, 034503 (2018).