アントラセンの拡張されたビスチアサンチリデンの高安定性ディラジカル状態の3状態切り替え

Marco B S Wonink¹, Brian P Corbet¹, Artem A Kulago¹

¹Stratingh Institute for Chemistry and Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

Journal of the American Chemical Society

|October 25, 2021

まとめ

研究者は光,電気,熱で制御可能な安定したダイラジカルを含む 3つの状態を持つ新しい分子スイッチを開発しましたこの突破は記憶装置のような機能的な材料の開発の可能性を提供しています

科学分野:

分子電子と材料科学
有機化学と超分子化学です

背景:

マルチステーブルな分子システムは機能的な高度な材料の開発に不可欠です
複数の刺激で分子状態を制御することは,分子工学における重要な課題です.

研究の目的:

アントラセンの拡張されたビスチアサンチリデンを基にした新しい多安定分子スイッチングシステムを報告する.
電気化学,熱化学,光化学刺激を用いて 3つの異なる分子状態の制御を証明する.
ダイラジカル状態とディケーション状態の性質と安定性を調査する.

主な方法:

アントラセンの拡張されたビスシアキサンチリデンの合成
状態を相互変換する電気化学的特徴.
紫外線照射 (385 nm) を用いた光化学的切り替え
電子パラマグネティック共振 (EPR) スペクトロスコーピーは,ダイラジカル状態を特徴づけます.

主要な成果:

3つのアドレッシブルな状態を持つシステム: 閉じたシェル,開いたシェルダイラディカル,およびディケーション.
安定したダイラジカルは,高活性化バリア (25.7 kcal mol−1 at 293 K) による運動安定性を表している.
電気化学的,熱的,光化学的方法によって達成された状態間の可逆的な切り替え.

結論:

報告された分子システムは,複数のアクチュエータを介して堅固なマルチスタビリティと制御を示しています.
安定したダイラジカルと切り替え可能なシステムは,新しい機能的材料の設計に大きな希望を持っています.
潜在的な応用には,分子記憶装置,論理ゲート,有機フィールド効果トランジスタ (OFET) が含まれる.

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