On the crystal structure of the ordered vacancy compound Cu3In5Te9

Abstract

The crystal structure of the ordered vacancy compound (OVC) Cu3In5Te9 was analyzed using powder X-ray diffraction data. Several structural models were derived from the structure of the Cu-poor Cu-In-Se compound b-Cu0.39In1.2Se2 by permuting the cations in the available site positions. The refinement of the best model by the Rietveld method in the tetragonal space group P2c (Nº 112), with unit cell parameters a = 6.1852(2) Å, c = 12.3633(9) Å, V = 472.98(4) Å3, led to Rp = 7.1 %, Rwp = 8.5 %, Rexp = 6.4 %, S = 1.3 for 162 independent reflections. This model has the following Wyckoff site atomic distribution: Cu1 in 2e (0,0,0); In1 in 2f (½,½,0), In2 in 2d (0,½,¼); Cu2-In3 in 2b (½,0,¼); in 2a (0,0,¼); Te in 8n (x,y,z).