Structure refinement of the incommensurate composite crystal Sr1.145TiS3 through the Rietveld analysis process

The structure of the incommensurate composite crystal of the trigonal sulfide Sr1.145TiS3, Mr = 244.42, has been analyzed on the basis of the four-dimensional superspace group P1sR3m using powder X-ray diffraction data and the Rietveld analysis process. The unit cell and other crystal data are a1 = a2 = 11.5108 (2), a3 = 2.99094 (5) A, σ = [0 0 0.57227 (2)], V = 343.19 A3, Dx = 3.548 Mg m-3 and Z = 3. Rwp was 0.104 on an incommensurate modulated structure model with 47 structural parameters. The crystal is composed of columns of face-shared polyhedra, (TiS6/2)∞, and rows of Sr, and both are parallel to the c axis. (orig.)