The phosphorus-rich variety of ellenbergerite (Mg0.61Ti0.08vacancy0.31)2 (Mg0.52Al0.43vacancy0.05)12 [SiO3(O0.29(OH)0.71)]6 [(P0.71Si0.20vacancy0.09) O3OH]2(OH)6 was studied by X-ray diffraction and IR spectroscopy. The structure was refined in sp. gr. P63mc to R = 0.0248. The structure of phosphorus-rich ellenbergerite retains the octahedral framework observed in the structures of ellenbergerite, phosphoellenbergerite, ekatite, and a series of structurally related synthetic compounds. The structure of phosphorus-rich ellenbergerite differs from the structure of ellenbergerite primarily in that the Mg and Al cations in the phosphorus-rich variety are disordered in the octahedra of the framework, thereby leading to higher symmetry, and the channels of triangular cross section are occupied predominantly by P tetrahedra.
Crystal structure of phosphorous-rich ellenbergerite
PASERO, MARCO;MERLINO, STEFANO;
2007-01-01
Abstract
The phosphorus-rich variety of ellenbergerite (Mg0.61Ti0.08vacancy0.31)2 (Mg0.52Al0.43vacancy0.05)12 [SiO3(O0.29(OH)0.71)]6 [(P0.71Si0.20vacancy0.09) O3OH]2(OH)6 was studied by X-ray diffraction and IR spectroscopy. The structure was refined in sp. gr. P63mc to R = 0.0248. The structure of phosphorus-rich ellenbergerite retains the octahedral framework observed in the structures of ellenbergerite, phosphoellenbergerite, ekatite, and a series of structurally related synthetic compounds. The structure of phosphorus-rich ellenbergerite differs from the structure of ellenbergerite primarily in that the Mg and Al cations in the phosphorus-rich variety are disordered in the octahedra of the framework, thereby leading to higher symmetry, and the channels of triangular cross section are occupied predominantly by P tetrahedra.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
