Martin Andrew, Green Jason R, Thuo Martin
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC, 27695, USA.
Center for Complex Particle Systems, North Carolina State University, Raleigh, NC, 27695, USA.
Angew Chem Int Ed Engl. 2025 Jun 2;64(23):e202502197. doi: 10.1002/anie.202502197. Epub 2025 Mar 31.
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.
考兹曼悖论(KP)表明,深度过冷液体的熵可能低于相应的结晶固体。虽然这种熵灾变已通过平衡热力学进行了深入研究,但凝固过程是远离平衡发生的。通过对这一过程进行实验和理论分析,我们表明,核壳颗粒(CSPs)中的表面化学形态(合金成分不同物种的氧化驱动生成和自组织)能够将熵产生扰动到一定程度,使得连续平衡相变无法发生。表面的形态导致相关应力矢量发散,产生非平衡通量并阻碍均匀形核,从而导致深度过冷。形态衍生表面张量的不对称使最小熵产生准则发生偏斜。我们分析了一组非平衡模型,一个显示熵灾变,另一个避免熵灾变。将热力学速度限制应用于这些模型,我们表明KP呈现出另一种形式。偏离速度限制会使玻璃的构型熵发散,但添加一个界面态可避免在显著大的过冷度下出现熵灾变。