Exploring the effect of magnetic field on crystallization process and revealing the mechanism of magnetic field can enrich the regulation and intensification methods of crystallization process. In this paper, the effect of magnetic field on crystal nucleation and growth and its mechanism were comprehensively studied from the perspective of crystallization thermodynamics and kinetics, using a small organic molecule polyamide 56 salt as the model compound. The solubility, nucleation kinetics, and growth kinetics of the polyamide 56 salt were measured in the absence and presence of magnetic field, respectively. It was found that the magnetic field can improve the solubility of the model compound. The introduction of magnetic field can result in solubilization effect and enhance the directional motion of particles which can weaken the solute–solvent interaction. In addition, the introduction of magnetic field will prolong the nucleation induction period, widen the metastable zone width, and increase the nuclear barrier, which is the result of the competition between the directional motion of particles induced by the magnetic field and the inherent random Brownian motion. Moreover, the magnetic field can also effectively affect the crystal morphology and particle size, which is the result of the synergistic effect of nucleation kinetics and growth kinetics.

中文翻译：

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磁场对有机小分子结晶影响的机理研究

探索磁场对结晶过程的影响，揭示磁场的作用机制，可以丰富结晶过程的调控和强化方法。本文以有机小分子聚酰胺56盐为模型化合物，从结晶热力学和动力学的角度综合研究了磁场对晶体成核和生长的影响及其机制。分别在磁场不存在和存在下测量了聚酰胺 56 盐的溶解度、成核动力学和生长动力学。发现磁场可以提高模型化合物的溶解度。磁场的引入会导致增溶效应并增强颗粒的定向运动，从而削弱溶质 - 溶剂相互作用。此外，磁场的引入会延长成核诱导期，加宽亚稳区宽度，增加核势垒，这是磁场引起的粒子定向运动与固有随机布朗运动竞争的结果。运动。此外，磁场还可以有效地影响晶体形貌和粒径，这是成核动力学和生长动力学协同作用的结果。这是由磁场引起的粒子的定向运动与固有的随机布朗运动之间竞争的结果。此外，磁场还可以有效地影响晶体形貌和粒径，这是成核动力学和生长动力学协同作用的结果。这是由磁场引起的粒子的定向运动与固有的随机布朗运动之间竞争的结果。此外，磁场还可以有效地影响晶体形貌和粒径，这是成核动力学和生长动力学协同作用的结果。