Figure 10
Unit cells of centred lattices in reciprocal space. Assuming the unit cell to be a parallelepiped defined by the basis vectors a*, b* and c*, for A*, B*, C* and I* only half of all the unit-cell corners, for R* only one-third and for F* only a quarter are occupied by lattice points. The shortest translation vectors t* [blue arrows between (filled) lattice points] are commonly not parallel to the basis vectors. |