近赤外線,高不対称性の有機カイロプティックスイッチ
Si Tong Bao1, Shayan Louie1, Haoyu Jiang1
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|December 18, 2023
まとめ
研究者は新しいキラル分子リドックススイッチ (cPDI) [1]を開発し,UV-可視-NIR領域にわたって高強度,ブロードバンドのキロプティックスイッチを提供した. このPDIベースのトウィスタセンは,安定した可逆的なスイッチングを可能にし,高度な光学アプリケーションの可能性を実証しています.
科学分野:
- 有機化学
- 材料科学
- スペクトロスコーピー
背景:
- キラルの分子スイッチは,高度な光学アプリケーションに不可欠です.
- 調整可能なカイロプティック特性を有する材料の開発は依然として大きな課題です.
- 以前のPDIベースの材料は有望であったが,広波長応答と高いスイッチング幅が欠けていた.
研究 の 目的:
- PDIベースのツィスタセネを基にした新しいキラル分子リドックススイッチを合成し,特徴づけること.
- 波長範囲の広い範囲で新しい材料のカイロプティックスイッチング行動を調査します.
- 固体材料の応用の可能性を調査する
主な方法:
- チラルPDIベースのツイスタセンの二酸化物 (cPDI[2]) の合成
- UV-VisとCircular Dichroism (CD) を含むスペクトル分析
- 電気化学的還元とスイッチング行動の特徴.
- 密度関数理論 (DFT) の計算
主要な成果:
- cPDI[2]は,高強度およびブロードバンドキラル応答 (UV-Vis-NIR) を示す.
- 容易で安定し,逆戻り可能な多状態のカイロプティック・スイッチングは700 nm近くで観察される.
- 960 nmでのCD反応の有意な増加 (∆r∆εr > 300 M−1 cm−1) と高い非対称性因子 (3 × 10−2)
- DFT計算は,長波CD信号の起源を明らかにする.
結論:
- cPDI[2]は,優れた性能を持つユニークなカイロプティックスイッチとして機能します.
- 物質の分子歪みは,固体スイッチングのためのイオン拡散を容易にする.
- 高度な非対称性因子と,高度なカイロプティックデバイスのNIR応答位置cPDI [1]
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