Two New Layered Thioantimonate (III) Compounds: Solvothermal Syntheses, Crystal Structures, and Properties of (trans-1,4-C_6N_2H_(15))Sb_3S_5 and (trans-1,2-C_6N_2H_(15))Sb_3S_5·H_2O

摘要

Two new thioantimonate(III) compounds (trans-1,4-chxnH)Sb_3S_5 (I) and (trans-1,2-chxnH)Sb_3S_5.H_2O (II) (chxn = diaminocyclohexane = C_6N_2H_(14)) were prepared under solvothermal conditions. Structure-directing arrangements of the organic molecules are formed under the conditions of synthesis; these consist of hydrogen-bonded chains (I) and of double chains of the amine molecules indirectly joined by water molecules through hydrogen bonding (II). In both compounds the structure-directing counter-ions are arranged in a layer-like fashion and because of the similar arrangements the topologies of the thioantimonate(III) layers ~2_(infinity)[Sb_3S_5]~- are nearly identical. The anionic layers are formed by interconnection of SbS_3 trigonal pyramids and SbS_4 moieties. The layers containing Sb_2S_2, Sb_4S_4, and Sb_(10)S_(10) heterorings as secondary building units are stacked parallel to the b axis. The anionic layers and the structure-directing aggregates are stacked in a sandwich-like fashion. The water molecule in II can be removed at low temperatures, and this process is partially reversible. Interestingly, the removal of water is accompanied by a pronounced colour change from bright yellow to red.