Figure 4 Schematic representation of the hk0 reciprocal section of Nd2Ti2O7. The monoclinic twin components, m1 and m2, are represented by black and red colour, respectively. The doubled monoclinic unit cell, S, determined by Scheunemann & Müller-Buschbaum (1975), and Harvey et al. (2005) is given in green colour. The c* axes of all modifications are perpendicular to the paper.  [article HTML]