From One-Dimensional Ribbon to Three-Dimensional Microporous Framework: The Syntheses, Crystal Structures, and Properties of a Series of Mercury Antimony Chalcogenides

In the presence of various organic amines/alkali metal cations or [TM(amine)m]n+ complexes as templates or structure-directing agents, a series of mercury antimony chalcogenide compounds have been solvothermally synthesized and structurally characterized. The compound [(Me)2NH2]2HgSb8S14 (1) features a one-dimensional (1D) [HgSb8S14]n2n− ribbon built from two 1D-[Sb4S7]n2n− chains bridged by HgS2 units. The compounds [enH2]0.5HgSbS3 (2) (en = ethylenediamine), [tetaH2]0.5HgSbS3 (3) (teta = triethylenetetramine), [1,2-pdaH]HgSbS3 (4) (1,2-pda = 1,2-diaminopropane), and [Ni(en)3]0.5HgSbS3 (5) feature two-dimensional (2D) layers of [HgSbS3]nn− with different structural motifs. The compound [tetaH2]0.25Rb0.5HgSbSe3 (6) exhibits a three-dimensional (3D) microporous framework structure of [HgSbSe3]nn− with cationic [tetaH2]2+ and Rb+ located in the channels. The optical absorption spectra indicate that all the compounds are semiconductors, with estimated bandgaps of 2.03 eV for 1, 2.49 eV for 2, 2.40 eV for 3, 2.55 eV for 4, 2.68 eV for 5, and 1.42 eV for 6, respectively. Thermal stabilities of these compounds have been investigated via thermogravimetric analyses.