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Abstract Kauzmann paradox (KP) suggests that deeply supercooled liquids can have a lower entropy than the corresponding crystalline solids. While this entropy catastrophe has been thoroughly studied via equilibrium thermodynamics, the solidification process occurs far‐from‐equilibrium. By analyzing this process experimentally and theoretically, we show that surface chemical speciation (oxidation‐driven generation and self‐organization of different species of the alloy components) in core‐shell particles (CSPs) can perturb the entropy production to an extent that a continuum equilibrium phase transition is not possible. Speciation of the surface causes divergence of associated stress vectors that generate nonequilibrium fluxes and frustrates homogeneous nucleation hence deep undercooling. The asymmetry of the speciation‐derived surface tensor skews the minimum entropy production criterion. We analyze a set of nonequilibrium models, one showing and one averting the entropy catastrophe. Applying thermodynamic speed limits to these models, we show that the KP takes another form. Deviations from the speed limit diverge the configurational entropy of the glass, but adding an interfacial state avoids the entropy catastrophe with significantly large supercooling.
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Energy Conversion and Entropy Production in Biased Random Walk Processes—From Discrete Modeling to the Continuous Limit
We considered discrete and continuous representations of a thermodynamic process in which a random walker (e.g., a molecular motor on a molecular track) uses periodically pumped energy (work) to pass N sites and move energetically downhill while dissipating heat. Interestingly, we found that, starting from a discrete model, the limit in which the motion becomes continuous in space and time (N→∞) is not unique and depends on what physical observables are assumed to be unchanged in the process. In particular, one may (as usually done) choose to keep the speed and diffusion coefficient fixed during this limiting process, in which case, the entropy production is affected. In addition, we also studied processes in which the entropy production is kept constant as N→∞ at the cost of a modified speed or diffusion coefficient. Furthermore, we also combined this dynamics with work against an opposing force, which made it possible to study the effect of discretization of the process on the thermodynamic efficiency of transferring the power input to the power output. Interestingly, we found that the efficiency was increased in the limit of N→∞. Finally, we investigated the same process when transitions between sites can only happen at finite time intervals and studied the impact of this time discretization on the thermodynamic variables as the continuous limit is approached.
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- Award ID(s):
- 1953701
- PAR ID:
- 10454231
- Date Published:
- Journal Name:
- Entropy
- Volume:
- 25
- Issue:
- 8
- ISSN:
- 1099-4300
- Page Range / eLocation ID:
- 1218
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/e25081218
