发表机构
CNRS; Ecole polytechnique; Institut Polytechnique de Paris（法国国家科学研究中心; 巴黎综合理工学院; 巴黎理工学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究扩展经典成核理论，建立多变量成核模型，揭示非经典凝聚路径，发现模型表现优于经典理论，明确经典理论适用范围并为其完善提供基础。
AI 中文摘要
我们扩展了经典成核理论（CNT），明确纳入成核的多维特性以及动力学与热力学的耦合作用。具体而言，我们在尖锐界面和弥散界面两种描述框架下，将团簇密度视为独立变量，其中动力学由动力学密度泛函理论支配。将该理论应用于 Lennard-Jones 体系中的液体凝聚时，我们的双变量（尺寸-密度）和三变量（尺寸-界面宽度-密度）模型揭示了非经典成核机制：在低过饱和度下，两种模型均恢复经典图像，即团簇以平衡液体密度成核并生长；随着过饱和度升高，非经典行为出现，表现为临界团簇密度降低，成核路径涉及团簇尺寸、密度的协同演化，且在弥散界面描述中还包含界面宽度的变化，弥散界面模型显示高过饱和度下界面弥散度快速增加；在旋节线极限附近，两种模型均预测临界团簇尺寸发散、密度趋近亚稳初始相的密度、形成功消失，实现了成核与旋节线分解的平滑衔接。与分子动力学模拟的对比表明，两种模型的表现均显著优于 CNT，但仅弥散界面模型能捕捉到极低过饱和度下观测到的临界团簇密度的弱非单调依赖关系。总体而言，研究结果表明 CNT 仅适用于低过饱和度区间，本工作为其在该区间之外的完善提供了坚实基础。
英文摘要
We extend classical nucleation theory (CNT) by explicitly incorporating the multidimensional nature of nucleation and the coupled roles of kinetics and thermodynamics. Specifically, we treat the cluster density as an independent variable, within both sharp-interface and diffuse-interface descriptions. The kinetics are governed by dynamical density functional theory. Applied to liquid condensation in the Lennard-Jones system, our two-variable (size--density) and three-variable (size--interface width--density) models reveal nonclassical nucleation mechanism. At low supersaturation, both models recover the classical picture, in which clusters nucleate and grow at the equilibrium liquid density. As supersaturation increases, a nonclassical behavior emerges: the critical cluster density decreases, and the nucleation pathway involves concomitant evolution in cluster size, density, and, within the diffuse-interface description, interfacial width. Our model with diffuse interface reveals a rapid increase in interfacial diffuseness at high supersaturation. Near the spinodal limit, both models predict the critical cluster with diverging sizes, densities approaching that of the metastable initial phase, and vanishing work of formation, which provides a smooth connection between nucleation and spinodal decomposition. Comparison with molecular dynamics simulations demonstrates that both models substantially outperform CNT. However, the weak non-monotonic dependence of the critical cluster density observed at very low supersaturation is captured only by diffuse-interface models. Overall, our findings indicate that CNT should be applied only in the low-supersaturation regime, and our work provides a robust foundation for its refinement beyond this limit.
