熱的に堅固な四重奏の合成と薄膜 (S = 3/2) グラウンドステートトライラジカル
Chan Shu1, Maren Pink2, Tobias Junghoefer3
1Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States.
Journal of the American Chemical Society
|March 31, 2021
まとめ
合成された高スピン有機トライラジカルは,良好な熱安定性を持つ四重基底状態を示します. これらのトライラジカルは安定した薄膜を形成し,新興技術の潜在的応用を促進します.
科学分野:
- 有機化学
- 材料科学
- 量子化学について
背景:
- 高スピン有機トリラジカルは新興技術にとって有望です
- 既存のトライラジカルには,スピン状態と安定性の低い間の小さなエネルギーギャップがあります.
研究 の 目的:
- 有機トライラジカルを合成し特徴づけること
- 熱安定性,磁気性,薄膜形成能力を評価する.
主な方法:
- 合成のためのPd(0) -触媒化された根幹-根幹クロスカップリング反応.
- SQUID磁気測定と定量EPRスペクトロスコーピーは,磁気特性を決定する.
- 薄膜沈殿のための超高真空蒸発と分析のためのXPS,AFM,SEM.
主要な成果:
- クォーテット基底状態のトライラジカル (3) は,0.2-0.3 kcal mol−1と1.2-1.8 kcal mol−1のダブルクォーテットエネルギーギャップで合成された.
- トライラジカルは,室温で>70%のクォーテート状態の集団と>160 °Cの熱安定性を表しています.
- 無傷のトライラジカル薄膜は真空蒸発によって形成され,真空下での安定性を示したが,空気中での劣化を示した.ドロップキャストフィルムはより良い空気安定性を示した.
結論:
- 合成されたトライラジカルは オーガニックの高スピン分子に比べて 性能が向上しています
- 安定した薄膜を形成する能力は,デバイスのアプリケーションの道を開きます.
- 実用的な応用のために,空気に安定した配方に関するさらなる研究が必要である.
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