2012年4月
Raman and NMR spectroscopic characterization of high-pressure K-cymrite (KAlSi3O8 center dot H2O) and its anhydrous form (kokchetavite)
JOURNAL OF MINERALOGICAL AND PETROLOGICAL SCIENCES
- ,
- ,
- ,
- 巻
- 107
- 号
- 2
- 開始ページ
- 114
- 終了ページ
- 119
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.2465/jmps.111020i
- 出版者・発行元
- JAPAN ASSOC MINERALOGICAL SCIENCES
To facilitate identification of high-pressure K-cymrite (KAlSi3O8 center dot H2O) phase and its anhydrous form (kokchetavite) in natural rocks, we have synthesized both phases and have characterized them by micro-Raman and NMR spectroscopy. K-cymrite was synthesized at 5 GPa and 800 degrees C. Kokchetavite was obtained by dehydrating K-cymrite at ambient pressure and 550 degrees C. The H-1 MAS and H-1-Si-29 CP MAS NMR spectra of K-cymrite are consistent with the reported crystal structure that contains H2O molecules and has a disordered Si-Al distribution. The Raman spectra obtained under ambient conditions for K-cymrite (and kokchetavite) contain major peaks at 114.0 (109.1), 380.2 (390.0) and 832.5 (835.8) cm(-1). For K-cymrite, OH stretching vibration is also observed at 3541 cm(-1) with a shoulder at 3623 cm(-1). The Raman spectrum for kokchetavite is consistent with that previously reported for a natural sample found as inclusions in clinopyroxenes and garnets in a garnet-pyroxene rock. However, the data for K-cymrite are inconsistent with the Raman features of a previously reported "relict K-cymrite in K-feldspar" from an eclogite. Pressure- and temperature-dependencies of the Raman shifts for the strongest peak of both phases are also reported.
- リンク情報
- ID情報
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- DOI : 10.2465/jmps.111020i
- ISSN : 1345-6296
- eISSN : 1349-3825
- Web of Science ID : WOS:000303629200007