齐聚噻吩衍生物电致变色性质

合成了四种齐聚噻吩衍生物：5,5"-二氰基-2,2’:5’,2"-三噻吩 (DCN3T), 5,5"’-二氰基-2,2’:5’,2":5",2"’-四噻吩 (DCN4T), 5,5"’-甲氧基-2,2’:5’,2":5",2"’-四噻吩(DMO4T) 和 4,4"-二羧基-5,5"-二丙基-2,2’:5’,2"-三噻吩 (BP3T-DCOOH),研究了它们的电致变色性质,研究结果发现,这四种齐聚噻吩衍生物膜在电场作用下,可以发生可逆的颜色变化。

Benzene‐1,3,5‐tricarboxylate‐bridged Double‐layered Nickel(II) Complex with Ferromagnetically Coupled Ni3 Units

The reaction of benzene‐1,3,5‐tricarboxylic acid (H₃BTC) with NiCO₃ under hydrothermal conditions afforded a new 2D complex Ni₃(BTC)₂(µ‐H₂O)₂·6H₂O, which possesses an infinite double‐layered structure. The layer is comprised of syn‐syn carboxylate‐ and aqua oxygen‐bridged Ni₃ units that are connected further by BTC^3?. Ferromagnetic exchange interaction is operative between the Ni²⁺ ions, experimentally showing the propagation of ferromagnetic coupling through the syn‐syn carboxylate bridges because the magnetic exchange through the aqua bridges [Ni–O–Ni bond angle=122.8(3) °] is antiferromagnetic. On the basis of the present results and the previous reports on syn‐syn carboxylate‐bridged Ni(II) complexes, it was found that the coplanarity of Ni–O–C–O–Ni dominated the magnetism. The planar arrangement of Ni–O–C–O–Ni gives rise to strong antiferromagnetic coupling, whereas the deviation from planarity weakens the antiferromagnetic coupling, possibly resulting in weak ferromagnetic coupling. Therefore, similarly to the mixed ligand‐bridged Cu(II) dimer the orbital complementary effect (OCE) is also operative in the aqua‐/carboxylate‐bridged Ni(II) dimer.