The coordination chemistry of Zn(II), Cd(II) and Hg(II) complexes with 1,2,4-triazole derivatives

This perspective illustrates the coordination features of complexes constructed by 1,2,4-triazole derivatives and transition metal ions which belong to Group IIB, namely Zn(II), Cd(II) and Hg(II), demonstrates their behaviors in thermal stabilities, gas or liquid adsorption, fluorescence and nonlinear optical properties and also discusses the relation between their properties and crystal structures. Various 1,2,4-triazole derivatives containing versatile donor sites for coordination can be obtained through introducing different substituent groups to C3, N4 and C5 positions, thus offering rich coordination modes. The structures of these complexes rely on their triazole ligands, as well as mixed ligands, metal ions, anions and synthetic conditions. Obviously, the diversity in structure induces the controllability of properties, since the properties are influenced by several factors, which is significant for the applications of potential multifunctional materials.