Structural signature of the configurational entropy change during the glass formation of plastic crystal cyanoadamantane

Based on an analysis of the observed crystal structures of the phases of anhydrous sodium pyrophosphate, a calculation of the configurational entropy change of the system between the ordered ambient-temperature phase and the disordered hexagonal phase above 600 °C has been carried out. The result is 0.2187R cal mol−1 deg−1 where R is the gas constant.

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Phase equilibrium of PuO2−x−Pu2O3 based on first-principles calculations and configurational entropy change

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2011.03.034 ◽

2011 ◽

Vol 412 (3) ◽

pp. 338-341 ◽

Cited By ~ 3

Author(s):

Satoshi Minamoto ◽

Masato Kato ◽

Kenji Konashi

Keyword(s):

Phase Equilibrium ◽

First Principles ◽

Configurational Entropy ◽

Entropy Change ◽

First Principles Calculations

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Lattice model calculation of the configurational entropy change for athermal mixtures

Journal of Polymer Science ◽

10.1002/pol.1956.120199116 ◽

1956 ◽

Vol 19 (91) ◽

pp. 159-170 ◽

Cited By ~ 3

Author(s):

W. R. Krigbaum

Keyword(s):

Model Calculation ◽

Lattice Model ◽

Configurational Entropy ◽

Entropy Change

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Quantitative relations between cooperative motion, emergent elasticity, and free volume in model glass-forming polymer materials

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1418654112 ◽

2015 ◽

Vol 112 (10) ◽

pp. 2966-2971 ◽

Cited By ~ 103

Author(s):

Beatriz A. Pazmiño Betancourt ◽

Paul Z. Hanakata ◽

Francis W. Starr ◽

Jack F. Douglas

Keyword(s):

Free Volume ◽

Glass Formation ◽

Collective Motion ◽

Configurational Entropy ◽

Polymer Melt ◽

Polymer Materials ◽

Coarse Grained ◽

Glass Forming ◽

Cooperative Motion ◽

Glass Forming Materials

The study of glass formation is largely framed by semiempirical models that emphasize the importance of progressively growing cooperative motion accompanying the drop in fluid configurational entropy, emergent elasticity, or the vanishing of accessible free volume available for molecular motion in cooled liquids. We investigate the extent to which these descriptions are related through computations on a model coarse-grained polymer melt, with and without nanoparticle additives, and for supported polymer films with smooth or rough surfaces, allowing for substantial variation of the glass transition temperature and the fragility of glass formation. We find quantitative relations between emergent elasticity, the average local volume accessible for particle motion, and the growth of collective motion in cooled liquids. Surprisingly, we find that each of these models of glass formation can equally well describe the relaxation data for all of the systems that we simulate. In this way, we uncover some unity in our understanding of glass-forming materials from perspectives formerly considered as distinct.

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