(Mg,Fe) SiO3 四角格子ガーネットの精密格子パラメータ決定
まとめ
研究者らは,地球マントルの重要な鉱物である四角形のガーネットを,高圧下で合成した. 格子パラメータが決定され,鉄含有量に基づいてそのサイズを予測するための方程式が提供されました.
科学分野:
- ミネラル物理学 ミネラル物理学
- 地質化学 地質化学
- クリスタログラフィーです.
背景:
- テトラゴナル・ガーネット (Mg,Fe) SiO(3) は,高圧ピロキセンの相である.
- それは地球の上層マントルの重要な構成要素です.
- その結晶構造は立方ガーネットの歪んだバージョンであり,X線 difraktion パターンのマイナーライン分割につながります.
研究 の 目的:
- 組成が異なる四角形のガーネットを合成し,特徴づけること.
- 構成と格子パラメータの関係を見極めるために.
- MgSiO ((3) -FeSiO ((3))) システムにおける格子パラメータの予測方程式を提供する.
主な方法:
- 約20ギガパスカルと2000度Cのテトラゴナル・ガーネットの合成
- 粉末全体の分解を用いたX線粉末 difraktion データの分析.
- 消火したサンプルの格子パラメータ (a と c) の決定.
主要な成果:
- MgSiO ((3) -FeSiO ((3)) システムのMgSiO ((3) -FeSiO ((3)) 豊富な部分で,一連の四角形のガーネットを成功裏に合成しました.
- FeSiOのモル分数 (((3) (x) と格子パラメータの間の確立された線形関係.
- 微分方程式:a = 11.516 + 0.088x と c = 11.428 + 0.157x は,0.0 ≤ x ≤ 0.2.2 に対して
結論:
- この研究は,FeSiO ((3)) 含有量に基づいて四角形のガーネットの格子パラメータを予測するための正確な方程式を提供します.
- これらの発見は,地球のマントルの高圧鉱物の振る舞いの理解を高めています.
- 使用された方法は,複雑な結晶構造と重複する difraktion ピークを分析するのに有効です.
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