论文标题
在二聚体晶状体气体模型中竞争核的动力学控制
Kinetic control of competing nuclei in a dimer lattice-gas model
论文作者
论文摘要
成核是溶液合成新材料的关键步骤。建立良好的晶状体气体模型可用于洞悉涉及单核类型的成核途径的基本物理。在许多情况下，相对于多个沉淀阶段，溶液过饱和。这可以在相似的时间尺度上产生稳定和亚稳态核的种群，从而产生涉及两者之间竞争的复杂成核途径。在这项研究中，我们基于代表溶液中颗粒的两种相互作用二聚体引入了晶格加拿大模型。每种二聚体的每种二聚体都构成了特定的空间填充结构。我们的模型进行了调整，以至于稳定和亚稳态的相位在类似的时间尺度上成核。任何一种结构都可以首先成核，对二聚体迁移率敏感。我们通过向前畅通采样来计算这些成核速率，并演示如何使用所得数据来推断成核结果和途径。可能性包括稳定相位的直接成核，长期的亚稳态结晶石的统治以及仅在出现了亚稳态相的多个临界后核后稳定相成核的途径。
Nucleation is a key step in the synthesis of new material from solution. Well-established lattice-gas models can be used to gain insight into the basic physics of nucleation pathways involving a single nucleus type. In many situations a solution is supersaturated with respect to more than one precipitating phase. This can generate a population both stable and metastable nuclei on similar timescales and hence complex nucleation pathways involving competition between the two. In this study we introduce a lattice-gas model based on two types of interacting dimer representing particles in solution. Each type of dimer nucleates to a specific space-filling structure. Our model is tuned such that stable and metastable phases nucleate on a similar timescale. Either structure may nucleate first, with probability sensitive to dimer mobility. We calculate these nucleation rates via Forward-Flux Sampling and demonstrate how the resulting data can be used to infer the nucleation outcome and pathway. Possibilities include direct nucleation of the stable phase, domination of long-lived metastable crystallites, and pathways in which the stable phase nucleates only after multiple post-critical nuclei of the metastable phase have appeared.
