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 Sr 1.145 TiS 3 , M r =244.42, has been analyzed on the basis of the four-dimensional superspace group P R3m 1s using powder X-ray diffraction data and the Rietveld analysis process. The unit cell and other crystal data are a 1 =a 2 =11.5108 (2), a 3 =2.99094 (5) A, a=[000.57227 (2)], V=343.19 A 3 , D x =3.548 Mg m -3 and Z=3. R wp was 0.104 on an incommensurate modulated structure model with 47 structural parameters. The crystal is composed of columns of face-shared polyhedra, (TiS 6/2 )∞, and rows of Sr, and both are parallel to the c axis