ニュートラルなπ-ラジカル導体として共振で安定した1,2,3-ディチアゾール-1,2,3-ディチアゾリル

Leanne Beer¹, Jaclyn L Brusso, A Wallace Cordes

¹Contribution from the Department of Chemistry, University of Waterloo, Ontario N2L 3G1, Canada.

Journal of the American Chemical Society

|August 9, 2002

まとめ

研究者らは,8-クロロビス[1,2,3]ディチアゾール[4,5-b:5]から新しいラジカルを合成した.

科学分野:

マテリアルサイエンス材料科学
有機化学オーガニック・ケミストリー
固体物理固体物理学

背景:

Zwitterionicヘテロサイクルは,材料化学における多用途な構成要素である.
電荷伝送と分子間相互作用を理解することは,機能的な有機物質の設計に不可欠です.

研究の目的:

新規アルキル化ビス[1,2,3]ディシアゾール[4,5-b:5',4'-e]ピリジン (ClBP) のラジカルを合成し,特徴づけること.
これらのラジカルの結晶構造,伝導性,磁気性を含む固体状態の性質を調査する.
分子構造と観測された電子および磁気的振る舞いを相関させる.

主な方法:

8-クロロビス[1,2,3]ディシアゾール[4,5-b:5',4'-e]ピリジン (ClBP) のアルキル化に続いて還元.
サイクルボルトメトリー,EPRスペクトロスコーピー,X線結晶学,磁気感受性,導電性測定を用いた特徴付け.
B3LYP/6-31Gのガス相計算と拡張されたHückel帯の計算を含む計算分析.

主要な成果:

熱的に安定した結晶ClBPラジカル (ClBPR) の合成.
結晶構造は,重要な分子間S-S接触を持つ滑り出したpi-stackを明らかにします.
ClBPMe.で観測された室温伝導度 (10^-5から10^-6 S cm^-1) と弱い1Dの鉄磁性.
93KでのClBPMeの相変化が観察され,構造的に特徴づけられました.

結論:

電子および磁気特性は,ステリック障害の影響を受けた,滑り込んだpi-stackの弱い分子間重複に起因する.
この研究は,潜在的な電子アプリケーションのための有機ラジカルの構造-性質関係に関する洞察を提供します.
低クーロンビック障壁Uは,固体状態での電荷移転を容易にする.

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