Four novel linear trinuclear assemblies containing bridging triazole ligands. Crystal structure, magnetic, semiconducting and fluorescent properties

Four homotrinuclear linear coordination compounds with bridging ligand of (m-phenol)-1,2,4-triazole, [Mn3(L)6(H2O)6](ClO4)6 (1), [Ni3(L)6(H2O)6](BF4)6·4DMF (2), [Cd3(L)6(H2O)6](ClO4)6· 2H2O·2DMF·2EtOH (3), [Zn3(L)8(H2O)4](BF4)4(SiF6)·2EtOH·12H2O (4), have been synthesized and structurally determined. The structures consist of three metal ions in linear arrangements, linked to each other by two pairs of three N1, N2 bridging triazole ligands. The negative value of J suggests that antiferromagnetic interaction exists in 1. Green fluorescence of 2 and 4 with emissions at 518 nm for 2 and 524 for 4 is possibly assigned to LMCT. The energy gaps of the compounds 2 and 4 are 1.82 and 1.97 eV, respectively, which suggests that the two materials behave as semiconductors.