Liu Zhi-Kun, Yao Zi-Shuo, Tao Jun
Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Liangxiang Campus, Beijing Institute of Technology, Beijing 102488, People's Republic of China.
Inorg Chem. 2021 Jul 19;60(14):10291-10301. doi: 10.1021/acs.inorgchem.1c00727. Epub 2021 Jul 8.
Halogen-substituted Fe(III) compounds, [Fe(Hphsalpm)]PTFB (Hphsalpm = 5-X-(,)-((phenyl(2-pyridyl)methylimino)methyl)phenol, PTFB = phenyltrifluoroborate; X = F for , Cl for , Br for ) and [Fe(Hphsalpm)]PTFB·MeOH (X = I for ·MeOH), were synthesized. Compounds , ·MeOH, and its desolvated form exhibited an invariant high-spin state in the whole temperature range, while and underwent gradual, nonhysteretic, and incomplete spin crossover (SCO) with transition temperatures () of 153 and 220 K, respectively. Interestingly, the SCO-active compounds and showed light-induced excited spin-state trapping (LIESST) effects at 10 K, and light-induced reversible ON/OFF switching behaviors were realized by alternately using 880 and 1064 nm light, while the thermally inert compound ·MeOH unexpectedly showed a reverse-LIESST effect. These results may help to design and synthesize new photoresponsive SCO Fe(III) compounds for the development of switchable materials.
合成了卤素取代的铁（III）化合物，[Fe(Hphsalpm)]PTFB（Hphsalpm = 5-X-(,)-((苯基(2-吡啶基)甲基亚氨基)甲基)苯酚，PTFB = 苯基三氟硼酸盐；X = F时为 ，Cl时为 ，Br时为 ）以及[Fe(Hphsalpm)]PTFB·MeOH（X = I时为·MeOH）。化合物 、·MeOH及其去溶剂化形式 在整个温度范围内呈现出不变的高自旋态，而 和 则经历了逐渐的、非滞后的且不完全的自旋交叉（SCO），转变温度（）分别为153 K和220 K。有趣的是，具有SCO活性的化合物 和 在10 K时表现出光诱导激发自旋态捕获（LIESST）效应，并且通过交替使用880和1064 nm光实现了光诱导的可逆开/关切换行为，而热惰性化合物·MeOH意外地表现出反向LIESST效应。这些结果可能有助于设计和合成新型光响应性SCO铁（III）化合物以用于可切换材料的开发。
