Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.
Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Moruzzi 13, 56124, Pisa, Italy.
Chemistry. 2018 Sep 12;24(51):13556-13564. doi: 10.1002/chem.201802196. Epub 2018 Aug 20.
Circularly polarised luminescence (CPL) is a chiroptical phenomenon gaining more and more attention, as the availability of the necessary spectrometers is getting better and first applications in bioimaging or for the preparation of OLEDs (organic light emitting diodes) are coming within range. Until now most examples of distinctly CPL-active compounds were europium and terbium complexes though theoretically the electronic structure of samarium should be as suitable as the one of terbium. This discrepancy can be accounted for by the high susceptibility of samarium to non-radiative deactivation processes. The aim of this study was to strategically circumvent this difficulty by the use of a ligand scaffold which has already proven to efficiently suppress these processes, namely the cryptates. The prepared partly deuterated samarium and europium complexes exhibit distinct circularly polarised luminescence with dissymmetry factors up to g =+0.13 (Sm ) or g =-0.19 (Eu ).
圆偏振发光（CPL）是一种手性光学现象，越来越受到关注，因为必要的光谱仪的可用性越来越好，并且在生物成像或制备 OLED（有机发光二极管）方面的首次应用已经在范围内。到目前为止，最明显的 CPL 活性化合物的例子是铕和铽配合物，尽管从理论上讲，钐的电子结构应该与铽的电子结构一样合适。这种差异可以归因于钐对非辐射去活过程的高敏感性。这项研究的目的是通过使用一种已经被证明能够有效地抑制这些过程的配体支架来战略性地规避这一困难，即 cryptates。所制备的部分氘代钐和铕配合物表现出明显的圆偏振发光，不对称因子高达 g =+0.13（Sm）或 g =-0.19（Eu）。
