Three isomorphous metal–organic complexes with 1H-tetrazolyl-acetic acid (TAA), namely [M(TAA)2]n (M = MnII, 1, CoII, 2 and NiII, 3), have been synthesized under hydrothermal conditions. All the compounds were fully characterized by X-ray crystallography, elemental analysis, IR spectroscopy, thermal analysis and magnetic studies. The single crystal X-ray analyses show that the 1D chains of [M(COO−)2]n (M = MnII, 1, CoII, 2 and NiII, 3) are further joined by tetrazolyl spacers to form a 3D network. Based on the topological perspective, the complexes can be simplified into a (3,6)-connected 2-nodal net with (42.6)2(44.62.88.10) “ant” topology. The magnetic measurements reveal different magnetic exchange-coupling interactions: antiferromagnetic for 1 and ferromagnetic for 2 and 3. Furthermore, the magnetic measurements confirm that spin glass behaviour occurs in 3 but not in 2.
