Commins Patrick, Dippenaar A Bernard, Li Liang, Hara Hideyuki, Haynes Delia A, Naumov Panče
Smart Materials Lab, New York University Abu Dhabi PO Box 129188 Abu Dhabi United Arab Emirates
Department of Chemistry and Polymer Science, Stellenbosch University P. Bag X1 Matieland 7602 Republic of South Africa.
Chem Sci. 2021 Mar 26;12(17):6188-6193. doi: 10.1039/d1sc01246k.
Mechanically compliant organic crystals are the foundation of the development of future flexible, light-weight single-crystal electronics, and this requires reversibly deformable crystalline organic materials with permanent magnetism. Here, we report and characterize the first instance of a plastically bendable single crystal of a permanent organic radical, 4-(4'-cyano-2',3',4',5'-tetrafluorophenyl)-1,2,3,5-dithiadiazolyl. The weak interactions between the radicals render single crystals of the β phase of this material exceedingly soft, and the S-N interactions facilitate plastic bending. EPR imaging of a bent single crystal reveals the effect of deformation on the three-dimensional spin density of the crystal. The unusual mechanical compliance of this material opens prospects for exploration into flexible crystals of other stable organic radicals towards the development of flexible light-weight organic magnetoresistance devices based on weak, non-hydrogen-bonded interactions in molecular crystals.
机械柔顺性有机晶体是未来柔性、轻质单晶电子器件发展的基础，这需要具有永久磁性的可逆变形晶体有机材料。在此，我们报道并表征了首例具有永久磁性的有机自由基4-(4'-氰基-2',3',4',5'-四氟苯基)-1,2,3,5-二噻二唑基的可塑弯曲单晶。自由基之间的弱相互作用使该材料β相的单晶极其柔软，而S-N相互作用促进了塑性弯曲。弯曲单晶的电子顺磁共振成像揭示了变形对晶体三维自旋密度的影响。这种材料不同寻常的机械柔顺性为探索其他稳定有机自由基的柔性晶体开辟了前景，有望基于分子晶体中弱的非氢键相互作用开发柔性轻质有机磁阻器件。
