Cooperativity in plastic crystals
| Autor: | Marco Pieruccini, Elpidio Tombari |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Hydrogen bond Enthalpy Energy landscape Thermodynamics Cooperativity 02 engineering and technology Calorimetry 021001 nanoscience & nanotechnology 01 natural sciences 0103 physical sciences Relaxation (physics) Plastic crystal 010306 general physics 0210 nano-technology Glass transition |
| Zdroj: | Physical review. E 97 (2018). doi:10.1103/PhysRevE.97.032116 info:cnr-pdr/source/autori:Pieruccini M.; Tombari E./titolo:Cooperativity in plastic crystals/doi:10.1103%2FPhysRevE.97.032116/rivista:Physical review. E (Print)/anno:2018/pagina_da:/pagina_a:/intervallo_pagine:/volume:97 |
| ISSN: | 2470-0053 2470-0045 |
| DOI: | 10.1103/physreve.97.032116 |
| Popis: | A statistical mechanical model previously adopted for the analysis of the α-relaxation in structural glass formers is rederived within a general theoretical framework originally developed for systems approaching the ideal glassy state. The interplay between nonexponentiality and cooperativity is reconsidered in the light of energy landscape concepts. The method is used to estimate the cooperativity in orientationally disordered crystals, either from the analysis of literature data on linear dielectric response or from the enthalpy relaxation function obtained by temperature-modulated calorimetry. Knowledge of the specific heat step due to the freezing of the configurational or conformational modes at the glass transition is needed in order to properly account for the extent to which the relaxing system deviates from equilibrium during the rearrangement processes. A number of plastic crystals have been analyzed, and relatively higher cooperativities are found in the presence of hydrogen bonding interaction. |
| Databáze: | OpenAIRE |
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