Synthesis, thermal analysis and structural characterization of the ternary compound Ag2SnTe3

Abstract

The ternary compound Ag2 SnTe3 has been synthesized and investigated by means of X-ray powder diffraction and its structure has been refined by the Rietveld method. The thermal differential analysis indicates a melting point of 343 ºC for this compound. The powder pattern was composed by 86.5% of the principal phase Ag2 SnTe3 and 13.5% of a secondary phase identified as the binary SnTe. The compound Ag2 SnTe3 crystallizes in the monoclinic space group Cc (Nº 9), Z = 4, with unit cell parameters a = 7.4420(1) Å, b = 12.8377(1) Å, c = 7.4025(1) Å, ß = 109.54(1) °, and V =666.5(2) Å3. The refinement of 36 instrumental and structural parameters converged to Rp = 8.1 %, Rwp = 9.6 %, Rexp = 7.1 %, S = 1.4, for 5501 step intensities and 290 independent reflections. The structure of Ag2 SnTe3 can be described as an adamantane compound derivative of the sphalerite structure.