電子基底状態における光誘導電子スピン偏振の金属イオン制御
Martin L Kirk1,2, David A Shultz3, Ju Chen1
1Department of Chemistry and Chemical Biology, The University of New Mexico, Albuquerque, New Mexico 87131-0001, United States.
Journal of the American Chemical Society
|July 12, 2021
まとめ
クロモフォール・ラジカル・コンプレックスにおける金属イオンは,電子スピン極化 (ESP) を制御する. パラジウム複合体は弱い放射性ESPを示し,プラチナ複合体はスピン軌道相互作用により強い吸収性ESPを示します.
科学分野:
- 写真化学
- スピン化学
- 材料科学
背景:
- クロモフォール・ラジカル・コンプレックスは,光誘発電子スピン偏振 (ESP) を表している.
- これらの複合体の電子基底状態ダブルレット (2S0/D0) は金属イオンの影響を受ける.
- ナイトロニル酸化物 (NN) のような有機基は重要な成分です.
研究 の 目的:
- 金属イオン (Pd vs. Pt) の変化が,光誘発ESPのサインと強さにどのように影響するか調査する.
- これらの複合体における 放射性対吸収性ESPのメカニズムを理解する
- 電子トランジションとスピン・オービタ・カップリングと相関する.
主な方法:
- (bpy) M ((CAT-m-Ph-NN) コンプレックスとM = PdIIとPtIIの合成
- 可視光を用いた複合体の光刺激
- 電子スピン極化 (ESP) を検出し,定量化するための光譜分析.
主要な成果:
- Pd複合体とPt複合体は,光刺激により,電荷分離による二重興奮状態 (2S1) を形成する.
- パラジウム複合体 (1- Pd) の発光性ESPは弱かった.
- 強い吸収性ESPはプラチナ複合体 (1-Pt) で生成された.
結論:
- メタルイオンのアイデンティティは,ESPの種類と大きさを大きく制御します.
- ゼロフィールド分裂は パラジウム複合体の移行に影響します
- プラチナ複合体のスピン-軌道相互作用は,強い吸収ESPを生成するために不可欠です.
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