The diffraction data are of the gamma-form of o-Nitroaniline, C6H6N2O3. This compound is known to be polymorphic; the alpha-form is probably amorphous, while the beta- and gamma-forms are crystalline. Difficulties with the unit-cell determination of the gamma-form were reported as a consequence of twinning. These newly recorded diffraction data are of a twinned crystal. The raw data and processing with EVAL are described in details in IUCrData as a Raw Data Letter [Lutz & Kroon-Batenburg, IUCrData (2022]. The data were recorded on a Bruker ApexII diffractometer and stored as .sfrm files. They were also converted with Bruker imagesum.py script as part of the APEXII software to full .cbf files.

The raw data are described in an exemplary Raw Data Letter, with the goal of publishing and archiving raw diffraction data. Methods and software developers are invited to upload and re-use the data.