ペリレンダイミドスタックにおける幾何学と電子結合:構造と負荷の輸送関係をマッピングする
Josh Vura-Weis1, Mark A Ratner, Michael R Wasielewski
1Department of Chemistry and Argonne-Northwestern Solar Energy Research Center, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|January 26, 2010
まとめ
研究者は,ペリレンダイミド (PDI) ダイマーにおける電子結合を計算し,積み重ねの幾何学によって著しく変化することを発見しました. この研究は,有機薄膜トランジスタ (OTFT) の有望な PDI デリバティブを特定しています.
科学分野:
- 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
- オーガニック・エレクトロニクス
背景:
- ペリレンダイミド (PDI) 誘導体は,重要な有機半導体である.
- pi-stacked ダイマー電子結合を理解することは,有機薄膜トランジスタ (OTFT) の電荷輸送を最適化するための鍵です.
研究 の 目的:
- PDI二次元におけるスタッキング幾何学と電子結合の関係を調査する.
- 高性能OTFTアプリケーションのための有望なPDIデリバティブを特定する.
主な方法:
- M06-2X/6-31++G**を用いた量子化学計算が採用されました.
- 結合エネルギーと電子結合は,ダイマースタッキング幾何学の関数として体系的に分析されました.
- 電子コップリングは,様々なイミド置換による20のPDIデリバティブについて計算された.
主要な成果:
- PDIダイマーにおける電子コップリングは,浅い潜在エネルギー面の最小値による (数桁以上の) 変動が顕著である.
- 特定のイミド置換を伴ういくつかのPDIデリバティブは,非常に有利な電子結合値を示した.
- 結合エネルギーと電子結合の分析は,OTFTの有望な候補者を明らかにした.
結論:
- 積み重ねの幾何学は,PDIダイマーの電子結合に重大な影響を及ぼし,電荷輸送特性に影響を与えます.
- 結合エネルギーと電子結合を比較する計算戦略は,新しいOTFT素材の設計に有効です.
- このアプローチは,ペンタセンやポリチオフェン (poly ((thiophene)) の誘導体のような他のpi-stacked有機半導体にも適用できます.
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