Table 2. R values for the different structure models.

Included are R values for observed (obs; defined by I > 3) and all (all) reflections. Partial R values are given for the group of main and satellite (sat) reflections. Structure model A is based on the low-temperature commensurate structure; model B has been obtained by refinement with arbitrary but small initial values for the modulation amplitudes; and model C is obtained after refinement of the superflip solution.

Model	A	B	C
GOFobs	2.78	2.78	2.79
(all)	0.0449	0.0449	0.0451
(main)	0.0411	0.0412	0.0411
(sat)	0.1268	0.1266	0.1301
GOFall	2.08	2.08	2.08
(all)	0.0720	0.0718	0.0720
(main)	0.0425	0.0425	0.0425
(sat)	0.3661	0.3634	0.3663
No. of parameters	719	719	719