The spin-states and spin-crossover behaviour of iron(<scp>ii</scp>) complexes of 2,6-dipyrazol-1-ylpyrazine derivatives
作者:Jérôme Elhaïk、Victoria A. Money、Simon A. Barrett、Colin A. Kilner、Ivana Radosavljevic Evans、Malcolm A. Halcrow
DOI:10.1039/b210368k
日期:——
The single crystalline solvate [Fe(L2H)2][BF4]2·3CH3NO2 undergoes a similarly abrupt spin-state transition at 198 K. Polycrystalline [Fe(L2Me)2][BF4]2 and [Fe(L2Me)2][ClO4]2 are isomorphous with each other and also exhibit spin-state transitions at low temperature, although these are very different in form. In contrast, both salts of [Fe(L2Me2)2]2+ and [Fe(L2Mes)2]2+ are fully low-spin at 295 K. Single
[FeL 2 ] X 2 (L = 2,6-dipyrazol-1-ylpyrazine [L 2 H],2,6-bis 3-methylpyrazol-1-yl} pyrazine [L 2 Me],2, 6-双3,5-二甲基吡唑-1-基}吡嗪[L 2 Me 2 ]或2,6-双3- [2,4,6-三甲基苯基]吡唑-1-基}吡嗪[L 2 Mes ]; X - = BF 4 -或C10 4 - )中有所描述。溶剂游离的[Fe(L 2 H)2 ] [BF 4 ] 2和[Fe(L 2 H)2 ] [ClO 4 ] 2分别在223 K和208 K处表现出非常相似的突然自旋跃迁,表现出磁滞现象循环的3–5K。粉末衍射测量提供了有关这两种化合物的相关但不相同的晶胞,并暗示[Fe(L 2 H)2 ] [ClO 4 ] 2与[Fe(L 1 H )2 ] [BF 4 ] 2 (L 1H = 2,6-二