BccとFccの移行金属と合金:その理想的構造と歪んだ構造を説明する上で,ヤン=テラー効果が中心的な役割を果たす
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|April 25, 2002
まとめ
移行金属における体中心立方体 (bcc) と面中心立方体 (fcc) 構造を駆動する電子的要因を特定しました. 新しい緊密結合機能であるDeltaE ((スター) は,これらの構造の好みと不安定性を説明します.
科学分野:
- 固体物理と化学 固体物理と化学
- マテリアルサイエンス 材料科学
- コンピューティング・マテリアル・デザイン
背景:
- 移行金属は通常,体中心の立方体 (bcc) と面中心の立方体 (fcc) の結晶構造を形成する.
- これらの構造の電子的起源を理解することは,材料設計において極めて重要です.
研究 の 目的:
- 移行金属におけるbccおよびfcc構造のエネルギー好適性を決定する電子的要因を分析する.
- 電子構造と結晶構造の変形を結びつけるための理論的ツールを開発する.
主な方法:
- 定量密度関数理論 (DFT) の計算. 定量密度関数理論 (DFT) の計算. 定量密度関数理論 (DFT) の計算.
- 質的タイトバインディング (TB) 計算.
- 波媒星内の電子伝送効果を分析するために,新しい緊密な結合機能であるDeltaE ((スター) の開発.
主要な成果:
- DeltaE ((スター) 機能は,bccとfccの構造間のエネルギー差を合理化することに成功しています.
- bcc (原子あたり7〜9のバレンスの電子) とfcc (原子あたり5〜6のバレンスの電子) のシステムにおける不安定性に関与する特定の軌道を特定した.
- 移行金属の元素および合金におけるbccおよびfcc構造の普及を説明した.
結論:
- DeltaE (星) 関数は,構造を決定する変形に関する軌道視点を提供します.
- 電子構造,特に波媒星内の電子伝達は,bccとfcc相の安定性を決定する.
- シンメトリー喪失に基づく金属構造の理論は,材料の行動に関する新しい洞察を提供します.
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