A novel 3D self-penetrating framework self-assembled from interweaving double-helical chains

摘要

Hydrothermal reaction of the flexible V-shaped ligand 3,3',4,4'-diphenylsulfone tetracarboxylic acid (H4dpstc) with nickel salt in the presence of long-chain N-donor ligand affords a fascinating entangled network, [Ni2(dpstc)(bim)2(H2O)]·2H2O (1) (bim = 1,4-bis(imidazol-1-yl)butane). Complex 1 represents an unusual 3D self-penetrating entangled framework, which is based on novel 2D helical layers. More interestingly, the 2D helical layers are constructed by the intertwined homo-axis covalent helices running along the same crystallo-graphic 21 axis in the b direction. Furthermore, the magnetic properties of complex 1 have been studied by measuring its magnetic susceptibility in the temperature range 2-300 K.