As,Sb,Biの高圧行動に関する比較研究
Ulrich Häussermann1, Karin Söderberg, Rolf Norrestam
1Department of Inorganic Chemistry, Stockholm University, S-10691 Stockholm, Sweden. ulrich@inorg.su.se
Journal of the American Chemical Society
|December 19, 2002
まとめ
高圧は,ヒ素,アンチモニー,ビスムスの複雑な構造を明らかにします. 彼らの安定性は,変異したバレンスの状態ではなく,静電と帯域エネルギーのバランスから生じる.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- コンピューティング・ケミストリー
背景:
- グループ15の元素 (As,Sb,Bi) は,高圧下では複雑な構造的振る舞いを表しています.
- Bi-III構造は,不均衡な調節によって特徴づけられる顕著な高圧相である.
研究 の 目的:
- グループ15のより重い元素の高圧構造的相変遷を研究する.
- 高圧相,特にBi-III構造の安定性を支配する電子的およびエネルギー的要因を解明する.
主な方法:
- Ab initio 密度関数計算. 最初から密度関数計算.
- 精密なシミュレーションのために,擬似電位と平面波ベースセットを使用した.
- 複雑なBi-III構造をモデル化するために超細胞近似を用いた.
主要な成果:
- スーパーセルを用いたホスト・ゲスト構造の実験的な圧力安定度範囲を成功裏に再現した.
- As,Sb,Biの電子構造における増加するs-dハイブリッド化が圧力で観察されましたが,低レベルです.
- Bi-III構造の安定性は,静電と帯域エネルギー貢献のバランスに起因する.
結論:
- 圧力によって引き起こされるバレンスの状態の変化は,複雑な中間圧力構造の出現を説明しません.
- グループ15のより重い元素におけるBi-III構造の安定性は,静電と帯域エネルギー貢献の繊細な相互作用の結果である.
- 静電および帯域エネルギーの両方のコンポーネントは,中間圧力の範囲における構造的安定性にとって同等に重要である.
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