Alkylamine-Templated Niccolite Frameworks of [GaIIIMII(HCOO)6]− (M = Fe, Ni): Structure, Magnetism, and Dielectricity
journal contributionposted on 12.03.2018, 17:17 by Kai Wang, Jian-Bo Xiong, Bin Xia, Qing-Lun Wang, Yu-Zhang Tong, Yue Ma, Zhe-Ming Wang, Song Gao
The five heterometallic formate frameworks [EtA][GaIIIFeII(HCOO)6] (1; EtA = CH3CH2NH3+), [DMA][GaIIIFeII(HCOO)6] (2; DMA = (CH3)2NH2+), [DEtA][GaIIIFeII(HCOO)6] (3; DEtA = (CH3CH2)2NH2+), [MA][GaIIINiII(HCOO)6] (4; MA = CH3NH3+), and [DMA][GaIIINiII(HCOO)6] (5) were synthesized through solvothermal methods. Complexes 1–5 are isotructural, and all crystallize in the trigonal P3̅1c space group. Each metal center is 6-connected, with each HCOO– bridging ligand in an anti-anti mode to build a three-dimensional niccolite-like architecture. All of the complexes exhibit weak ferromagnetism at low temperature. A variable-temperature (VT) dielectric study indicates that the dielectric anomaly is induced by the freezing of motions from the protonated amines during the freezing process.