Wang Jun-Li, Liu Qiang, Meng Yin-Shan, Zheng Hui, Zhu Hai-Lang, Shi Quan, Liu Tao
State Key Laboratory of Fine Chemicals, Dalian University of Technology , 2 Linggong Rd., 116024 Dalian, China.
Thermochemistry Laboratory, Liaoning Province Key Laboratory of Thermochemistry for Energy and Materials, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China.
Inorg Chem. 2017 Sep 5;56(17):10674-10680. doi: 10.1021/acs.inorgchem.7b01633. Epub 2017 Aug 16.
The existence of a correlation between spin crossover and dielectric properties is a hot topic in the field of multiresponse materials, which has potential applications in the memory devices, switches, and sensors. One formidable challenge is the simultaneous and rapid on/off switching of spin states of the spin carriers and magnetic coupling between them, which is crucial for both reversible photomagnetic behavior and variations in dielectric properties. Here, we report a dinuclear Fe(II) spin crossover complex, wherein each Fe(II) center exhibits an interconversion between Fe (HS = high-spin) and Fe (LS = low-spin) achieved upon heating and cooling. Moreover, the spin state of respective Fe(II) ions and the antiferromagnetic interaction between them can be switched bidirectionally under alternating irradiation with 532 and 808 nm light, resulting in interconversion between paramagnetic and diamagnetic properties. Interestingly, the spin crossover can also induce variations in dielectric tensors. This result provides a strategy to simultaneously and bidirectionally switch spin state, magnetic coupling, and dielectric properties using external stimuli.
自旋交叉与介电性质之间的相关性是多响应材料领域的一个热门话题，这类材料在存储设备、开关和传感器方面具有潜在应用。一个巨大的挑战是自旋载流子的自旋态及其之间的磁耦合要同时且快速地进行开/关切换，这对于可逆光磁行为和介电性质的变化都至关重要。在此，我们报道了一种双核Fe(II)自旋交叉配合物，其中每个Fe(II)中心在加热和冷却时都会在Fe(HS = 高自旋)和Fe(LS = 低自旋)之间发生相互转换。此外，在532和808 nm光的交替照射下，各个Fe(II)离子的自旋态及其之间的反铁磁相互作用可以双向切换，从而导致顺磁和抗磁性质之间的相互转换。有趣的是，自旋交叉还能引起介电张量的变化。这一结果提供了一种利用外部刺激同时双向切换自旋态、磁耦合和介电性质的策略。
