A study of the thermal and light induced spin transition in [FeL2](BF4)2 and [FeL2](ClO4)2 L=2,6-di(3-methylpyrazol-1-yl)pyrazine.
A study of the thermal and light induced spin transition in [FeL2](BF4)2 and [FeL2](ClO4)2 L=2,6-di(3-methylpyrazol-1-yl)pyrazine.
复制标题
[FeL2](BF4)2 和 [FeL2](ClO4)2 L=2,6-di(3-methylpyrazol-1-yl)pyrazine 中热和光诱导自旋跃迁的研究。
作者：
V. A. Money;J. Elhaïk;I. Radosavljević Evans;M. Halcrow;J. Howard
自旋交叉化合物[FeL_2]（BF_4）_2、L= 2，6-二（3-甲基吡唑-1-基）吡嗪和[FeL_2]（ClO_4）_2具有非常不寻常的两阶段自旋跃迁，它们最初是陡峭的，然后逐渐变缓。详细的变温单晶X射线衍射研究表明，自旋跃迁的过程是由反阴离子的有序-无序转变控制的。高自旋态和低自旋态都属于四元空间群I4，分别在290和30 K下呈现出高自旋态和低自旋态的结构。在30 K下，用波长分别为632.8和532.06 nm的红光或绿色激光照射标题化合物，发现它们发生了光诱导激发自旋态俘获（LIESST）.在此温度下，四氢呋喃光诱导亚稳高自旋态的晶胞参数为：[FeL 2]（ClO 4）2的a= 9.169（6），c= 17.77（1）A，单位晶胞体积增加21 A3;[FeL 2]（BF 4）2的a= 9.11（1），c= 17.75（2）A，体积增加42.8 A3。
The spin crossover compounds [FeL2](BF4)2, L=2,6-di(3-methylpyrazol-1-yl)pyrazine and [FeL2](ClO4)2 have very unusual two stage spin transitions which are initially steep and then become more gradual. A detailed variable temperature single crystal X-ray diffraction study has shown that the course of the spin transition is controlled by an order-disorder transition in the counter anions. The high and low spin states both crystallise in the tetragonal space group I4, the structures of the high and low spin states are presented at 290 and 30 K, respectively. The title compounds are shown to undergo LIESST (Light Induced Excited Spin State Trapping) under irradiation with either red or green laser light with wavelengths of 632.8 and 532.06 nm, respectively, at 30 K. The cell parameters for the tetragonal photo-induced metastable high spin state at this temperature are a= 9.169(6), c= 17.77(1) A for [FeL2](ClO4)2 with an increase in unit cell volume of 21 A3, and a= 9.11(1), c= 17.75(2) A and an increase in volume of 42.8 A3 for [FeL2](BF4)2.