Publication Date:
2015-01-01
Description:
The framework of the minerals belonging to the cancrinite-sodalite supergroup is very flexible and adapts itself to a wide range contents of extra-framework anions, giving rise to complex structures with different stacking sequences of layers that contain six-membered rings of tetrahedra. The knowledge of the crystal chemistry of these minerals was the key for the structure solution of a new phase showing a sequence with 18 layers. Geometrical and chemical constraints were imposed to the positions of the six-member rings so limiting the number of possible non-equivalent sequences of the 18 layers. The more probable sequences were single out on the basis of the chemical data and used as starting model vs. single crystal X-ray intensity data. The new 18-layer phase, ideal chemical formula (Na, K, Ca)
Print ISSN:
2194-4946
Electronic ISSN:
2196-7105
Topics:
Geosciences
,
Physics
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