ダイヤモンド sp (((2) の理解に向けて - 不飽和ダイヤモンドオリゴーマーモデルの欠陥

Tatyana S Zhuk¹, Tatyana Koso², Alexander E Pashenko¹

¹⊥Department of Organic Chemistry, Kiev Polytechnic Institute, pr. Pobedy 37, 03056 Kiev, Ukraine.

Journal of the American Chemical Society

|April 28, 2015

まとめ

研究者はダイアモンド型ダイマーとトリマーを合成し,sp(2) -欠陥を持つダイヤモンドをモデル化しました. DFTとab initioの研究では,電子構造が非局所化されることが明らかになり,ダイヤモンドのような材料の高電荷移動性を説明しました.

科学分野:

* マテリアルサイエンス
* コンピュータ化学
* ナノテクノロジー

背景:

*ナノメートルのサイズのダイヤモンドの断片であるダイアモンドオイドは,材料科学において極めて重要です.
* ダイヤモンドの表面のsp(2) - 欠陥は,電荷の移動性などの材料特性に影響します.
* ダイアモンド型モデルの電子構造を理解することは,物質の振る舞いを制御する鍵です.

研究の目的:

* sp{2}-欠陥のあるダイヤモンドのモデルとしてダイヤモンド型ジマーとトリマーを合成し,特徴づけること.
*これらのダイアモンド型オリゴーマーとその基質カチョンの電子構造と自己組立特性を調査する.
* ダイヤモンド型材料の表面改変のためのC−H結合の機能化を探求する.

主な方法:

* ダイアモンド型ジマーとトリマーの合成は,対応するケトンのマクマリー結合による.
* スペクトル検査と結晶検査を用いた特徴付け.
*密度関数理論 (DFT) とab initio (MP2) の方法を用いた計算研究.

主要な成果:

*ナノメートルのサイズのダイアモンド型ジマーとトリマーの準備と特徴付けに成功しました.
* DFTとab initio方法は,実験的幾何学とイオン化ポテンシャルを正確に再現しました.
* ヴァン・デル・ワールズの複合体は高度に非局所化され,対称的な電子欠乏構造を示しており,これは重要なシグマ非局所化を示している.

結論:

* ダイアモンド型オリゴマーの観察されたシグマ移転は,pi移転系と比較できます.
*非局所的なsp(2)-欠陥は,ダイヤモンドのような材料における高い表面電荷移動に寄与する.
* 機能化されたダイアモンド誘導体 (ハロゲン,ヒドロキシ) が得られ,さらに表面の付着と改変を可能にしました.

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