School of Chemistry and Material Science, Shanxi Normal University, Linfen, P R China.
Dalton Trans. 2013 May 14;42(18):6611-8. doi: 10.1039/c3dt32539c.
Three novel tetrazole-based frustrated magnets, namely, Co3(OH)2(3-ptz)2(SO4)(H2O)4 (1), Co2(OH)(tzba)(H2O)4 (2) and [Co(OH)(tta)] (3) (3-ptz = 5-(3-pyridyl) tetrazole, H2tzba = 4-(1H-tetrazol-5-yl) benzoic acid, Htta = 1H-tetrazole) were hydrothermal synthesized and magnetically characterized. Compound 1 is a 2D (4,4) layered structure assembled by sulfate capped triangular [Co3(μ3-OH)(μ3-SO4)] clusters and in situ synthesized μ3-3-ptz ligands. Compound 2 features Co3(μ3-OH) triangle based magnetic Δ-chains linked with in situ generated μ5-tzba ligands to form a 2D layer. Compound 3 is a uninodal eight-connected body-centered-cubic (bcu) 3D network with square Co4O4 clusters as nodes and μ4-tta ligands as linkers. Interestingly, spin frustration was observed in these complexes due to inherent spin competition in triangle, Δ-chain and square. Magnetic studies show that 1 behaves as antiferromagnet, while 2 and 3 exhibits spin canting and long-range magnetic ordering.
三种新型基于四唑的受挫磁体，即 Co3(OH)2(3-ptz)2(SO4)(H2O)4（1）、Co2(OH)(tzba)(H2O)4（2）和[Co(OH)(tta)]（3）（3-ptz = 5-(3-吡啶基)四唑，H2tzba = 4-(1H-四唑-5-基)苯甲酸，Htta = 1H-四唑），是通过水热合成得到的，并对其进行了磁性表征。化合物 1 是由硫酸根封端的三角形[Co3(μ3-OH)(μ3-SO4)]簇和原位合成的μ3-3-ptz 配体组装而成的二维（4,4）层状结构。化合物 2 具有基于 Co3(μ3-OH)三角形的磁性Δ链，与原位生成的μ5-tzba 配体相连，形成二维层。化合物 3 是具有正方形 Co4O4 簇作为节点和μ4-tta 配体作为连接体的单节点八连接体心立方（bcu）3D 网络。有趣的是，由于三角形、Δ链和正方形中固有的自旋竞争，这些配合物中观察到了自旋受挫。磁性研究表明，1 表现为反铁磁性，而 2 和 3 则表现出自旋倾斜和长程磁有序。
