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Published on: December 4, 2017
Thermodynamic manifestations of structure fluctuations in liquids
Alexander Z Patashinski1, Mark A Ratner
1Department of Chemistry, and Materials Research Center, Northwestern University, Evanston, Illinois 60208, USA.
Abstract:
Fluctuations of pressure and internal energy in a low-temperature liquid, generated by structure fluctuations, are related in a general and straightforward way to the differences between the long- and short-time thermodynamic susceptibilities. The relations are similar to, but not identical with, those between thermodynamic fluctuations and susceptibilities in classical statistical mechanics. The derivation is general and straightforward, and based on the assumption that the local structure is a slow-relaxing mode in low-temperature liquids and may be characterized by an order parameter.
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