Pseudosymmetry in Trinitropyrazole: The Cost of Error in Space-Group Determination

摘要

With more than 9 of crystal structures having several independent species (Z' > 1) in an asymmetric unit (with the number of examples increasing over the years) and 27 of them showing approximate symmetry elements, the pseudosymmetry phenomenon has become a widely recognized disaster in the solid-state world that significantly complicates the scientific efforts of many chemists and crystallogra-phers.