U4O9: atoms in general sites giving the hkl extinctions of special sites

Acta Crystallogr A. 2004 Jul;60(Pt 4):318-21. doi: 10.1107/S0108767304012188. Epub 2004 Jun 24.


In U4O9, most of the atoms are in general 48-fold [48(e)] sites of the space group I43d and yet the hkl reflections obey the extinction rules for atoms occupying special 12-fold [12(b)] sites. An explanation is given for this effect, which can be generalized to any space group.