Two unprecedented NLO-active coordination polymers constructed by a semi-rigid tetrahedral linker†
Abstract
The assemblies of tetrahedral linker tetrakis[4-(carboxyphenyl)oxamethyl]methane acid (H4L) with ZnCl2 and CdBr2 yield two noncentrosymmetric, NLO-active coordination polymers [Zn4(L2)(H2O)3(DMA)]·2H2O (1) and [Cd2L(DMA)2(H2O)2] (2), respectively. 1 has an unprecedented 2-fold interpenetrating sxa topology with ferroelectric properties, while 2 has a 7-fold interpenetrating dia network.