International
Tables for
Crystallography
Volume A
Space-group symmetry
Edited by M. I. Aroyo

International Tables for Crystallography (2015). Vol. A, ch. 1.5, p. 82

Figure 1.5.1.9 

H. Wondratscheka and M. I. Aroyob
[Figure 1.5.1.9]
Figure 1.5.1.9

Rhombohedral lattice with a triple hexagonal unit cell a, b, c in obverse setting (i.e. unit cell a1, b1, c in Fig. 1.5.1.6[link]c) and the three centred monoclinic cells. (a) C-centred cells [C_{1}] with [a_{1}, b_{1}, c]; [C_{2}] with [a_{2}, b_{2}, c]; and [C_{3}] with [a_{3}, b_{3}, c]. The unique monoclinic axes are [b_{1}, b_{2}] and [b_{3}], respectively. The origin for all four cells is the same. (b) A-centred cells [A_{1}] with [a', b_{1}, c_{1}]; [A_{2}] with [a', b_{2}, c_{2}]; and [A_{3}] with [a', b_{3}, c_{3}]. The unique monoclinic axes are [c_{1}], [c_{2}] and [c_{3}], respectively. The origin for all four cells is the same. The fractions indicate the height of the lattice points along the axis of projection.