Hydrazine-Assisted Syntheses and Properties of Mercury Tellurides Containing Transition-Metal Complexes.

With assistance of reactive and coordinative hydrazine, transition-metal telluromercurates [Mn(trien)(NH)][HgTe] (A), [Zn(trien)(NH)]HgTe (B), [Mn(tepa)(NH)]HgTe (C), [TM(trien)(HgTe)] (TM = Mn (D), Zn (E)), and [Zn(atep)]HgTe (atep = 4-(2-aminoethyl)triethylenetetramine) (F) were solvothermally prepared in triethylenetetramine (trien) or tetraethylenepentamine (tepa) solvents using elemental Te as precursor in lower temperature range. Compounds A and B consist of mixed coordination cations [TM(trien)(NH)] (TM = Mn, Zn) and one-dimensional polyanion [HgTe] with the five-membered HgTe rings being coplanar. Compound C is composed of two [Mn(tepa)(NH)] cations and a [HgTe] cluster with a centrosymmetric structure. Compounds D and E consist of coordination polymer [TM(trien) (HgTe)] containing novel doubled [HgTe] chain with tetrahedrally coordinated Hg(II) centers, which is quite different from the common single chain with the same composition of [HgTe]. D and E are the first examples of telluromercurates incorporated with TM complex units via TM-Te bonds. Compound F contains fivefold coordinated [Zn(atep)] cations and zigzag [HgTe] polymeric anion. The [HgTe] anion is a new species of the binary telluromercurates. It is built from [HgTe] and [HgTe(Te)] subunits via interconnectivity, which generates HgTe and HgTe rings in the structure. Compounds A-F are potential semiconductors with narrow band gaps in the range of 0.96-1.09 eV. Photocatalytic investigation of Mn(II) complexes show that they are photocatalytically active in the degradation of CV under visible-light irradiation with the highest catalytic effective of cluster compound C.