论文标题
旋转跨界材料和框架中多步过渡的结构 - 陶艺关系和多步过渡的机制
Structure-property relationships and the mechanisms of multistep transitions in spin crossover materials and frameworks
论文作者
论文摘要
自旋跨界框架和分子晶体表现出迷人的集体行为。这包括具有滞后的多步过渡以及高旋转和低自旋金属中心的各种远程有序模式。从实际和基本的角度来看，了解这些集体行为背后的机制非常重要。我们研究了一个简单的弹性相互作用模型，并确定了36个不同的自旋状态阶阶段。我们观察到一到八个步骤之间的自旋状态过渡。这些包括尖锐的过渡和跨界，以及完整和不完整的自旋跨界。我们展示了解释这些差异的结构核关系。这些之所以出现，是因为整个键相互作用是抗铁弹性的（有不同自旋态的金属中心）。而通过空间相互作用通常是铁弹性（有利于同一自旋状态）。通常，具有较长范围弹性相互作用的刚性材料会导致具有更多步骤和更多样化的自旋状态订购的过渡，这解释了为什么两者在框架中都是突出的。
Spin crossover frameworks and molecular crystals display fascinating collective behaviours. This includes multi-step transitions with hysteresis and a wide variety of long-range ordered patterns of high-spin and low-spin metal centres. From both practical and fundamental perspectives it is important to understand the mechanisms behind these collective behaviours. We study a simple model of elastic interactions and identify thirty six different spin-state ordered phases. We observe spin-state transitions with between one and eight steps. These include both sharp transitions and crossovers, and both complete and incomplete spin crossover. We demonstrate structure-property relationships that explain these differences. These arise because through-bond interactions are antiferroelastic (favour metal centres with different spin-states); whereas, through-space interactions are typically ferroelastic (favour the same spin-state). In general, rigid materials with longer range elastic interactions lead to transitions with more steps and more diverse spin-state ordering, which explains why both are prominent in frameworks.
