分子フレームワークの同質的な批判的行動 Zn (((CN) 2とCd (((imidazolate) 2
Ines E Collings1, Andrew B Cairns, Amber L Thompson
1Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, United Kingdom.
Journal of the American Chemical Society
|April 24, 2013
まとめ
亜鉛 ((II) シアン化物とカドミウム ((II) イミダゾラートにおける構造的歪みは,負の熱膨張に関する洞察を示している. これらの発見は,分子フレームワークの熱力学が,梱包効率と動的不安定性に依存することを示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- クリスタルグラフィーです.
背景:
- 亜鉛 ((II) シアン化物 (Zn ((CN) 2) とカドミウム ((II) イミダゾラート (Cd ((im) 2) のような分子構造は,複雑な構造的行動を示す.
- 外部刺激に対する反応を理解することは,高度な材料の設計に不可欠です.
研究 の 目的:
- Zn (CN) 2とCd (im) 2.の温度と圧力による構造的相変遷を調査する.
- Zn(CN) の負の熱膨張の背後にある原子機構を解明する2.
- フレームワークのトポロジー,梱包効率,熱力学的性質の関係を探求する.
主な方法:
- 単一結晶と粉末X線 difraktion測定を用いた.
- 変数温度と変数圧力に関する研究が行われました.
- 原子の移動と構造的歪みの分析が行われました.
主要な成果:
- Zn(CN) 2は,第1次位移相相から,1.52 GPaでオーソロンビック相へと移行する.
- 原子の移動には,Zn中心の四面体の相関する傾きが含まれ,負の熱膨張を説明します.
- Cd(im) 2は,圧力下にある Zn(CN) 2で観察されたように,温度変化に対して同様の機械的反応を示しています.
結論:
- この研究では,負の熱膨張と関連した,圧力誘発による Zn(CN) 2 の相変化が明らかになりました.
- Zn(CN) 2とCd(im) 2の機械的振る舞いは,熱力学の共通の支配原理を示唆しています.
- パッキング効率とダイナミックフレームワークの不安定性は,分子フレームワークの熱力学における重要な要因です.
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