八核円 Eu ((III) ヘリケートの可視円状偏光
Yan Bing Tan1, Yoshinori Okayasu2, Shohei Katao1
1Graduate School of Science and Technology, Division of Materials Science, Nara Institute of Science and Technology, NAIST, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Journal of the American Chemical Society
|September 22, 2020
まとめ
この研究では,ユニークな正方形の反プリズム構造を持つ新型のキラル八核円状ランタニドヘリケートを導入しました. これらの複合体は 強い円形の偏光を発し 先進的な光学材料への道を開きます
科学分野:
- 協調化学
- 超分子化学
- フォト物理学
背景:
- ランタニド (LnIII) 複合体は,発光アプリケーションに不可欠である.
- チラルのヘリケートは 独特の構造と光物理的特性を有しています
- 先進的な光学技術では,円形の偏光 (CPL) が不可欠です.
研究 の 目的:
- 新しいD4対称八核円状ランタニドヘリケートを合成し,特徴づけること.
- CPL活動を含む構造的特徴と光物理的性質を調査する.
- キラル光学材料におけるこれらのヘリケートの潜在能力を探求する.
主な方法:
- キラル bis ((4-イソプロピル-2-オクサゾリニル) ピリジン (iPr-Pybox) とトライアニオン型トリス-β-ディケトネート (THP) リガンドを EuIIIと TbIIIを用いた八核円状ヘリケートの合成.
- X線結晶学による構造的特徴.
- 光学的な特徴は,光輝度と円形の偏光光度 (CPL) を含む.
主要な成果:
- 正方形の反プリズム構造を持つ8核の円形ヘリケート (RとS) の成功形成
- EuIIIおよびTbIIIヘリケートは,リガンド刺激時に特徴的なf-f発光を示す.
- 高排出量 (EuIII: 0.145,TbIII: 0.0013 クロロフォーム) と有意なCPL活動 (EuIIIでは1.25まで)
結論:
- リガンドの設計は,明確に定義されたキラル八核円状ヘリケートの形成を可能にします.
- これらのヘリケートは効率的な発光と強いCPLを示し,キラルフォトニックの応用の可能性を示しています.
- 観測されたCPLの強度差は,高度な循環的に偏光した発光装置を開発する際の有用性を強調しています.
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