Scientists uncover pitfalls of letting algorithms determine crystal structures
Chemists warn not to blindly trust x-ray crystallography software after finding and correcting mistakes in iodine azide structures
Letting computers take the lead in crystal structure determinations could be generating more inaccurate structures than previously thought. After detecting discrepancies in the published crystal structures of two explosive iodine azide modifications, German researchers reanalysed the old diffraction data and corrected both structures.1
‘The reported structures show a suspicious misorder – others call it disorder – with half-occupied atomic positions and partially colliding atoms,’ says Ulrich Müller, an emeritus professor at the University of Marburg who led the study together with Stephan Schulz from the University of Duisburg–Essen.