A refinement of Elba dachiardite: Opposite acentric domains simulating a centric structure
نویسنده
چکیده
The crystal structure of Elba dachiardite shows an unusual rotation of two tetrahedra around one edge. This rotation gives rise to two configurations which have the same frequency thus maintaining the statistical symmetry C2/m. The most probable distribution of ions indicates the presence of two cation sites and five water molecules. One cation site is at the crossing of the two systems of channels and is 8-fold coordinated, the other is in the channel parallel to c and is 2-fold coordinated. The extraframework sites are not affected by the rotation within the framework, coordinating only the fixed framework oxygens.
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