发表机构
Pusan National University（釜山国立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过结合精确窗口投影与惯性独立粒子参考扩展有限体积计数框架，揭示1:1溶剂原始模型中集体离子扩散的表观理想性源于结构负贡献与动力学正贡献的补偿，并表明耦合场描述可改善高浓度下的扩散估计。
AI 中文摘要
理解集体离子输运如何从平衡涨落中涌现是电解质统计力学的核心问题。有限体积涨落为获取这一信息提供了一条可行途径，但其解释因混合了波数与集体场而变得复杂。在此，我们通过将精确窗口投影与惯性独立粒子参考相结合，扩展了用于推断集体离子扩散的有限体积计数框架，并将其应用于对称的1:1溶剂原始模型。在弹道区与平台区之间，离子数涨落的增长看似接近理想行为，但这种表面上的理想性源于负的结构超额贡献与正的动力学超额贡献之间的补偿。离子数-溶剂耦合弛豫进一步揭示了与溶剂相关和与溶剂正交投影之间的一种有符号再分配，而这种再分配在很大程度上隐藏于总响应之中。推断出的集体扩散依赖于观测长度和动力学闭合方式：仅凭实测结构并不能系统性地改善估计，而耦合场描述则减小了高浓度下的偏差。这些结果为分析具有相互耦合的离子数、电荷和溶剂涨落的更真实电解质提供了基础。
英文摘要
Understanding how collective ion transport emerges from equilibrium fluctuations is central to electrolyte statistical mechanics. Finite-volume fluctuations provide an accessible route to this information, but their interpretation is complicated because they mix wave numbers and collective fields. Here, we extend the finite-volume counting framework for inferring collective ion diffusion by combining the exact window projection with an inertial independent-particle reference, and apply it to a symmetric 1:1 solvent primitive model. The growth of ion-number fluctuations between the ballistic and plateau regimes appears nearly ideal, but this apparent ideality results from compensation between negative structural and positive dynamical excess contributions. The coupled ion-number--solvent relaxation further reveals a signed redistribution between solvent-associated and solvent-orthogonal projections that is largely hidden in the total response. The inferred collective diffusion depends on observation length and dynamical closure: measured structure alone does not systematically improve the estimate, whereas the coupled-field description reduces the high-concentration discrepancy. These results provide a basis for analyzing more realistic electrolytes with mutually coupled ion-number, charge, and solvent fluctuations.
Comments13 pages, 6 figures
