Image showing the alternative lattices. (a) Diffraction pattern showing the a*b* planes, with the area shown in the lower panels indicated by a white box. Predicted reflection positions of the alternative lattices twin domain 1 and twin domain 2 are shown in the lower left and right panels, respectively. (b) Schematic representation of the two alternative lattices of the β-Gal crystal viewed along the b axis. The real and reciprocal lattices are indicated in black and red, respectively.