A study of the 8466 structures reported in Inorganica Chimica Acta: 52 space group changes and their chemical consequences

260 structures published in Inorganica Chimica Acta present some problem about their crystal and molecular symmetry, moreover 41 compounds have been already corrected in this journal or in other journals. The unavailability of the structure factors tables has prevented a complete correction, in fact, we have reached a definitive result only for 52 crystalline compounds. These are divided into five categories: (A) incorrect Laue Group (19 examples), (B) omission of a centre of symmetry (20 examples), (C) incorrect Laue group and omission of a centre of symmetry (one example) (D) omission of a centre of symmetry coupled with a failure to recognize systematic absences (10 examples) and finally (E) non-space group translations (two examples). Moreover, other 44 examples of non-space group translations might be present, but we have not reached a definitive result for the unavailability of the structure factor tables.

During a single crystal structure determination some symmetry elements may go unrecognized. For example, the molecule reported in figure clearly shows a ternary axis that was lost during the X-ray study. The omission of symmetry elements (especially the centre of symmetry) results in poor molecular geometry, but sometimes more hidden errors (as false polymorphism) may be introduced. For these reasons, the structure results should be validated for missed higher symmetry before publication using appropriate programs as MISSYM, CHECKCIF or PLATON.Figure optionsDownload as PowerPoint slide