Design, synthesis, magnetic properties of a π-radical ligand with photo-excited high-spin state and its Fe(ii) complex. The first stage of a new strategy for LIESST materials
作者:Koichi Katayama、Masakazu Hirotsu、Isamu Kinoshita、Yoshio Teki
DOI:10.1039/c2dt31831h
日期:——
quartet state (S = 3/2) and its iron(II) complex [Fe(L11)H2B(Pz)2}2] (1) H2B(Pz)2− = dihydrobis(1-pyrazolyl)borate} were synthesized as a candidate for a new strategy for spin-crossover compounds exhibiting light-induced excited spin state trapping (LIESST), which is via the photo-excited high-spin state of the π-conjugated aromatic system. Control compounds, ligand L22 and [Fe(L22)H2B(Pz)2}2] (2), in
的π基团配体(9- [4-(6-氧代-1,5- dimethylverdazyl)苯基] -10- [5-(2,2'-联吡啶基)乙炔基]蒽,大号1 1)与可光兴奋高自旋四状态(小号= 3/2)和它的铁(II)配合物的[Fe(大号1 1)H 2 B(PZ)2 } 2 ](1)H 2 B(PZ)2 - =合成了二氢双(1-吡唑基)硼酸盐},作为一种新的自旋交叉化合物策略的候选物,该策略显示出光诱导的激发自旋态俘获(LIESST),这是通过π共轭芳族体系的光激发高自旋态。还合成了其中去除了L 1 1中的Verdazyl基团部分的对照化合物,配体L 2 2和[Fe(L 2 2)H 2 B(Pz)2 } 2 ](2)。通过时间分辨ESR技术证实了π自由基配体L 1 1的光激发四重态。从5 K到350 K研究了1和2的磁性行为的温度依赖性,表明在T处自旋交叉转变对于复合物1和2, c = 222