Solvothermal synthesis and characterization of MAgTeS3 (M=K, Rb) with layered structure

Two thio-tellurite KAgTeS3 (1) and RbAgTeS3 (2) were synthesized solvothermally and characterized by X-ray single crystal diffraction. These isostructural compounds compose of infinite parallel chains formed by AgS4 tetrahedra sharing their vertices, and these chains are further connected by trigonal-pyramidally coordinated Te4+ to form anionic layered structure with cations located between the layers. Crystal data for 1: M-r=370.75, P2(1)/c, a=0.73639(6) nm, b=1.06468(8) nm, c=0.85203(6) nm, beta=106.4640(10)degrees, V=0.64062(8) nm(3), Z=4, Mo K alpha, lambda=0.071073 nm, R(F-2)=4.44%, wR(F)=11.66%. Crystal data for 2: M-r=417.12, P2(1)/c, a=0.75531(12) run, b=1.07076(7) nm, c=0.8583(2) nm, beta=106.497(6)degrees, V=0.66558(19) nm(3), Z=4, Mo K alpha, lambda=0.071073 nm, R(F)=6.00%, wR(F-2)=15.43%. UV-Vis diffusion reflectance spectra suggest that the crystals 1 and 2 are semiconductor with estimated band gaps 2.03 and 2.10 eV, respectively. The DSC data show that crystal 1 and crystal 2 collapse at 333 and 352 degrees C respectively, in nitrogen.