Crystal Structure of the Na-, Ca-, Be-Cordierite and Crystallochemical Regularities in the Cordierite-Sekaninaite Series
- Moscow State University, Vorob'evy gory, Moscow, 119992 (Russian Federation)
- Philipps University, Marburg, (Germany)
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow oblast, 142432 (Russian Federation)
The crystal structure of the beryllium-rich cordierite [(Na{sub 0.28}Ca{sub 0.19})(H{sub 2}O){sub 0.92}](Mg{sub 1.86}Fe{sub 0.14}{sup 2-}) {center_dot} {l_brace}Al{sub 3.39}Be{sub 0.61}Si{sub 5}O{sub 18}{r_brace} was established by X-ray diffraction analysis (IPDS Stoe diffractometer, {lambda}MoK{sub {alpha}} radiation, graphite monochromator, 2{theta}{sub max} = 65 deg., R = 0.0186 for 1378 reflections): a = 16.850(3), b = 9.729(2), and c = 9.298(2) A; V = 1524.3(4) A{sup 3} , sp. gr. Cccm, Z = 4, and {rho}{sub calcd} = 2.655 g/cm{sup 3} . The numbers of Mg and Fe atoms isomorphously occupying the octahedral positions, Al and Be atoms in tetrahedra, and Na and Ca atoms and H{sub 2}O molecules in the framework cavities are refined. The hydrogen atom is localized and its coordinates and thermal displacement parameters are refined. Based on the comparative crystallochemical analysis of cordierites from different locations and origins, the regularities relating the unit-cell parameters b and c and the distortion index to the features of the chemical composition of the minerals under study are shown.
- OSTI ID:
- 20666223
- Journal Information:
- Crystallography Reports, Vol. 49, Issue 6; Other Information: Translated from Kristallografiya, ISSN 0023-4761, 49, 1049-1060 (No. 6, 2004); DOI: 10.1134/1.1828139; (c) 2004 MAIK ''Nauka / Interperiodica''; Country of input: International Atomic Energy Agency (IAEA); TN:; ISSN 1063-7745
- Country of Publication:
- United States
- Language:
- English
Similar Records
Crystal structure of britvinite [Pb{sub 7}(OH){sub 3}F(BO{sub 3}){sub 2}(CO{sub 3})][Mg{sub 4.5}(OH){sub 3}(Si{sub 5}O{sub 14})]: A new layered silicate with an original type of silicon-oxygen networks
Crystal structure of britvinite [Pb{sub 7}(OH){sub 3}F(BO{sub 3}){sub 2}(CO{sub 3})][Mg{sub 4.5}(OH){sub 3}(Si{sub 5}O{sub 14})]: A new layered silicate with an original type of silicon-oxygen networks