Organically templated chained chlorocadmates and cadmium-chloro thiocyanates

Abstract

With the protonated piperazine (pip) and triethylenediamine (1,4-diazabicyclo[2,2,2]octane, dabco) as the templates, two chained chlorocadmates [H₂pip][Cd₂Cl₆(H₂O)₂] 1, [H₂dabco][Cd₂Cl₆]·H₂O 2 and two chained cadmium-chloro thiocyanates [H₂pip][CdCl₃(SCN)]·2H₂O 3, [H₂dabco]₂[Cd₃Cl₈(SCN)₂]·H₂O 4 were obtained, and characterized by IR analysis, CHN analysis, TG analysis and X-ray single-crystal diffraction. The 1-D chain structure of compound 1 is the simplest, and can be described as a zigzag infinite extension of Cd octahedra via sharing the edges. Compound 2 shows a double-chain structure, comprising the dinuclear Cd₂Cl₉ subunits linked together via sharing the corners and the edges. Compounds 3 and 4 are the first examples of a family of organically templated chained cadmium-chloro thiocyanates. Compound 3 shows a linear-chain structure, comprising the Cd₂Cl₆ dimers by the SCN⁻groups, whereas compound 4 shows a stepped-chain structure, comprising the hexanuclear Cd₆Cl₁₆ subunits by the SCN⁻groups. Through intramolecular and intermolecular hydrogen-bonded interactions, all the title compounds are self-assembled into the 2-D or 3-D supramolecular networks. The fluorescence spectra show that compounds 1–3 possess fluorescence properties with emission peaks around 370 nm.