Due to the molecular symmetry of TTBI, each of the observed structures, as well as the global energy minimum, can be located in CSP searches in multiple space groups. Thus, we tested the search methods' ability to locate these structures in several space groups and we added two additional space groups (P 4 2 and P 4 2 /n) to our sampling as those in which the α polymorph is located. All other search parameters were the same as for the other single component crystals, except the perturbation cut-off for volume, which was increased to 200 Å 3 /atom due to the large molecular size. To investigate whether the temperature used to control the acceptance during basin hopping had an effect on finding target structures over such a large energy range, QR-BH was run at two temperatures: 3000 K (as above) and 500 K.