密度の高いリチウムオーライドの6p元素としての金
Guochun Yang1,2, Yanchao Wang1, Feng Peng1
1State Key Laboratory of Superhard Materials, Jilin University , Changchun 130012, China.
Journal of the American Chemical Society
|March 5, 2016
まとめ
高圧により,かつてないほど高い負の酸化状態を持つ金 (Au) 化合物が作られます. これらの新型オーライドは 独特の構造と性質を示し 金アニオンの化学的性質を拡張します
科学分野:
- 材料科学
- 固体化学
- コンピュータ化学
背景:
- 金 (Au) の負の酸化状態は稀ですが,鉄電性のようなユニークな性質を示しています.
- これまでの研究は,単原子アニオン黄金 (Au(-) をのみ確認した.
- 高度な負の酸化状態は,金にとって難解なままです.
研究 の 目的:
- 金に対してより高い負の酸化状態を達成する可能性を探求する.
- 高圧下でのアルカリ金属との反応を調査する.
- 異常なステキオメトリーと構造を持つ 金を含有する新種の化合物を発見する
主な方法:
- ファースト・プリンシパルの計算が採用された.
- 安定した段階を予測するためにスワーム構造の検索が利用されました.
- 高圧合成条件が提案された.
主要な成果:
- 高圧下では安定したリチウム濃度 (例えば,Li4Au,Li5Au) が予測された.
- これらの化合物は,Au中心の多面体とグラフェンのようなLi亜網を含むユニークな構造を特徴としています.
- これらの化合物の金原子は,高負の酸化状態を示し,6p元素として作用する.
- 圧力下でのセシウム (Cs) のような他のアルカリ金属と反応する黄金の同様の高負の酸化状態が観察されました.
結論:
- 高圧は高負酸化状態の金化合物を合成する有効な方法である.
- このアプローチにより,新しい構造モチーフを持つ多様な金アニオンを作成できます.
- この発見は 黄金基の材料の 奇妙な性質を探求するための 新たな道を開きます
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