Mn16SiC4とMn17Si2C4の構造におけるインターメタルとカーバイドドメイン間のエピタキシアル安定化
Rie T Fredrickson1, Yiming Guo1, Daniel C Fredrickson1
1Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 57306, United States.
Journal of the American Chemical Society
|December 8, 2015
まとめ
研究者らは,互換性のない結合モチーフを相互に増殖させることで,新しいインターメタルカルバイド Mn16SiC4 と Mn17Si2C4 を合成した. この"エピタキシアル安定化"は,金属系における課題を克服し,金属とカービッドの相互作用を織り交ぜた新しい材料を生み出します.
科学分野:
- 材料科学
- 固体化学
- クリスタルグラフィー
背景:
- 競合する幾何学的なモチーフや結合モチーフは,複雑な材料の構造と特性を理解するための鍵です.
- 柔らかい材料とは異なり,金属では部品の分離が困難である.
- 金属のガラス,磁気現象,大きな金属間ユニット細胞は 挫折の影響を受けます.
研究 の 目的:
- 金属系における互換性のない結合モチーフの相互増殖を誘導する方法を実証する.
- 交織型結合を示す新しいインターメタリックカルバイドを合成し,特徴づけること.
- これらの構造の安定化メカニズムを説明します.
主な方法:
- 新しいインターメタルカルバイドの合成:Mn16SiC4とMn17Si2C4.
- 合成された化合物の結晶構造の特徴.
- 安定力の調査のための密度関数理論 (DFT) 化学圧力分析.
主要な成果:
- Mn16SiC4 (mC42) と Mn17Si2C4 (mP46) という2つの新しいインターメタリックカービッドが成功して合成されました.
- これらの化合物は,Mn3C (カルバイド) とMn-Si (四面体密集) 領域の相互成長構造を示す.
- DFT分析では,Mn-SiとMn-CドメインのMn原子間の反対の局所圧力が,その相互成長によって緩和され,表軸安定化と呼ばれることが明らかになった.
結論:
- Mn16SiC4とMn17Si2C4の合成は,金属システムにおけるエンジニアの挫折への経路を提供します.
- エピタキシアル安定は,対極の局所圧力の緩和によって,相容れない結合モチーフを効果的に織り交わします.
- このアプローチは,特異な特性を持つ高度な材料を設計するための新しい戦略を提供します.
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