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Published on: June 9, 2023
Simultaneous Photo-Induced Magnetic and Dielectric Switching in an Iron(II)-Based Spin-Crossover Hofmann-Type
Nian-Tao Yao1, Liang Zhao1, Hui-Ying Sun1
1State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Ling gong Rd., 116024, Dalian, China.
Abstract:
Molecular materials possessing photo-tunable polarization switching is promising for optical switches, smart sensors, and data storage devices. However, it is challenging to devise a molecular material featuring simultaneous switchable magnetic and dielectric properties with regard to non-invasive and convenient light stimulus. Herein, we report a new Hofmann-type metal-organic framework (MOF) {Fe(bpt)[Pt(CN)4 ]} ⋅ 0.5anth (1, bpt=2,5-bis(4-pyridyl)thiophen; anth=anthracene), which displays thermo- and photo-switchable magnetic and dielectric properties. Photo-monitored structural analyses revealed that it was the photo-induced deformation of FeII coordination sphere and relative movement of guest anthracene that resulted in the variation of the local electric dipoles. These findings provide a new strategy to realize polarization switching through the light-induced spin crossover, and would be of fundamental significance for future photo-switchable and multifunctional materials.
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