Accurately predicting the spin crossover (SCO) temperature (T1/2) in spin crossover compounds remains a significant challenge, due to their extreme sensitivity to minor variations in ligand and crystal structure. In this study, we uncover a critical link between the redox potential of ligands and SCO behavior within Hofmann-type clathrates {Fe(R-pbpy+)2[µ2-M(CN)4]2} (R = electron-donating or electron-withdrawing groups, M = Pd or Pt). Through precise tuning of the ligands' electronic properties, we establish a correlation between redox potential, space group, and SCO temperature, explained by an adaptation of Marcus theory of electron transfer. These findings not only provide a deeper understanding of the factors governing SCO behavior but also present a promising strategy for the rational design of SCO materials with tailored properties.

中文翻译：

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阐明具有氧化还原活性配体的一系列亚铁配合物中氧化还原电位、自旋态和晶体结构之间的相关性

准确预测自旋交越化合物中的自旋交叉 （SCO） 温度 （T1/2） 仍然是一项重大挑战，因为它们对配体和晶体结构的微小变化极度敏感。在这项研究中，我们揭示了配体的氧化还原电位与霍夫曼型包合物 {Fe（R-pbpy+）2[μ2-M（CN）4]2}（R = 供电子或吸电子基团，M = Pd 或 Pt）内的 SCO 行为之间的关键联系。通过精确调整配体的电子特性，我们建立了氧化还原电位、空间群和 SCO 温度之间的相关性，这可以通过改编 Marcus 电子转移理论来解释。这些发现不仅提供了对控制 SCO 行为的因素的更深入理解，而且为合理设计具有定制性能的 SCO 材料提供了一种有前途的策略。