Refinement of the structure of b - U 4 O 9
نویسنده
چکیده
-U4O9 is a superlattice structure based on the ̄uorite arrangement of UO2. The U atoms occupy positions close to those in UO2 and the additional O atoms are accommodated in cuboctahedral clusters of 43m symmetry, which are centred on the special 12-fold sites of the cubic space group I 43d. The structure has been re®ned from single-crystal neutron data in accordance with the procedure described in the previous paper [Popa & Willis (2004). Acta Cryst. A60, 318±321].
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