International
Tables for
Crystallography
Volume B
Reciprocal space
Edited by U. Shmueli

International Tables for Crystallography (2010). Vol. B, ch. 2.5, p. 351   | 1 | 2 |

Figure 2.5.3.22 

M. Tanakaf
[Figure 2.5.3.22]
Figure 2.5.3.22

Schematic diffraction pattern at the [001] incidence of Sr2Nb2O7. Umweganregung paths a and b via fundamental reflections to the 0001 incommensurate reflection. Large and small spots denote fundamental and incommensurate reflections, respectively. The wave number vector of modulation is k = (½ − δ)a*.