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Article: Research from J. Hybler and co-researchers in the area of crystallography described.
- Article from:
- Journal of Technology
- Article date:
- November 17, 2009
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"The mineral kettnerite, CaBi(OFCO3), is a rare example of an order-disorder (OD) structure with a quadratic net. The lattice parameters of the simplest possible 1O polytype are a = 5.3641 (1), b = 5.3641 (1), c = 13.5771 (2) angstrom, and the space group is Pbaa," researchers in Prague, Czech Republic report.
"There are three kinds of OD layers, identical to structure-building layers. Two of them are non-polar: the Bi-O and Ca-Fat z = 0 and z = 1/2, respectively, with the layer-group symmetry C2/m2/m(4/a,b)2(1)/m2(1)/m. The third kind of OD layer of CO3 groups (located between the Bi-O and Ca-F layers) is polar, with alternating sense of polarity. The layer ...