English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/7806
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar otros formatos: Exportar EndNote (RIS)Exportar EndNote (RIS)Exportar EndNote (RIS)
Título : Thermal X-ray Diffraction Study of Chaorite from Russia
Autor : Matesanz, Emilio; García-Guinea, Javier ; Crespo Feo, Elena ; López-Arce, Paula; Valle Fuentes, Francisco José; Correcher, Virgilio
Palabras clave : Charoite
Structure
Dehydration
X-ray Diffraction
Differential thermal analysis
Thermogravimetry
Thermoluminescence
Fecha de publicación : 2008
Editor: Mineralogical Association of Canada
Citación : Canadian Mineralogist (2008) [in press]
Resumen: The effect of thermal annealing of charoite silicate K5 Ca8 (Si6O15) (Si2O7) (Si4O9) (OH)·3H2O have been studied by X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetry (TG) and thermoluminescence (TL). The chemical composition, analysed under electron probe micro-analysis (EPMA), indicates significant amounts of Na, Ba, Fe and F and the environmental scanning electron microscope (ESEM) results show impurities of unusual minerals such as tinaksite and aegirine. The cell parameters of both natural and preheated charoite, determined by XRD, are (i) a=[Å] 19.786(2); b=[Å] 32.003(3); c=[Å] 7.8565(9); α=90º; β=97.159º; γ=90º with a Snyder FOM of 7.1932 for the non-annealed sample and (ii) a=[Å] 19.567(2); b=[Å] 31.821(3); c=[Å] 7.1171(7); α=90º; β=94.000º(2); γ=90º; Snyder's FOM 6.2637 for the preheated charoite. The thermal effect supposes an axes shortening, of Δa=0.219[Å](2); Δb=0.182 [Å]; Δc=0.7394 [Å] and the β angle tilts only 3.159º. The DTA-TG and TL emission suggest: (i) a thermal gap of 80ºC-290ºC explained by charoite dehydration of different types of waters, i.e. hydrogen-bonded to the charoite lattice and non-bonded waters and (ii) the gap 290ºC-480ºC depicting a dehydroxylation processes.
Descripción : 19 pages, 4 figures.-- To be published in Canadian Mineralogist.
URI : http://hdl.handle.net/10261/7806
ISSN: 0008-4476
Aparece en las colecciones: (IGE) Artículos
(MNCN) Artículos
(ICV) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
2008charoitecanadianmineralogist.pdf2,28 MBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.