Fresh X-ray Data for Two Forms of Linear trans-quinacridone, C.I. Pigment Violet 19

Fresh X-ray data are given for the beta and gamma-forms of linear trans-quinacridone (C.I. Pigment Violet 19, C.I. 46500). These new data are better resolved than those reported previously. The new pattern of the gamma-form is compared with the previously reported pattern of gamma-form, and it is concluded that the latter pattern could be accounted for by better resolution of the former and the reports of the existence of the gamma-form should be treated with caution