The number and shape of lattice solvent molecules controls spin-crossover in an isomorphous series of crystalline solvate salts
The number and shape of lattice solvent molecules controls spin-crossover in an isomorphous series of crystalline solvate salts
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DOI：
10.1039/d1cc02624k
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发表时间：
2021-06-04
影响因子：
4.9
通讯作者：
Halcrow, Malcolm A.
中科院分区：
文献类型：
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作者：
Berdiell, Izar Capel;Kulmaczewski, Rafal;Halcrow, Malcolm A.
[FeL_2][BF_4](2)中心点nMeCN(L=N-(2，6-二{吡唑-1-基}吡啶-4-基)乙酰胺；n=1或2)与[FeL_2][ClO_4](2)中心点MeCN晶体同构。当n=1时，化合物在200K以下表现出突然的、滞后的自旋转变，但当n=2时，材料在冷却时保持高自旋。[FEL2]X-2中心点EtCN(X-=BF4-或ClO4-)与MeCN溶剂同构，并在几乎相同的温度下发生自旋转变。然而，这现在通过一个可重入的混合自旋中间相分两步进行，这与弯曲的丙腈分子的晶体有序性相关。
Crystals of [FeL2][BF4](2)center dot nMeCN (L = N-(2,6-di{pyrazol-1-yl}pyrid-4-yl)acetamide; n = 1 or 2) and [FeL2][ClO4](2)center dot MeCN are isomorphous. When n = 1 the compounds exhibit an abrupt, hysteretic spin-transition below 200 K, but when n = 2 the material remains high-spin on cooling. [FeL2]X-2 center dot EtCN (X- = BF4- or ClO4-) are isomorphous with the MeCN solvates and undergo their spin-transition at almost the same temperature. However this now occurs in two-steps via a re-entrant mixed-spin intermediate phase, which correlates with crystallographic ordering of the bent propionitrile molecule.