Benincori Tiziana, Arnaboldi Serena, Magni Mirko, Grecchi Sara, Cirilli Roberto, Fontanesi Claudio, Mussini Patrizia Romana
Dipartimento di Scienza e Alta Tecnologia , Università degli Studi dell'Insubria , Via Valleggio 11 , 22100 , Como , Italy.
Dipartimento di Chimica , Università degli Studi di Milano , via Golgi 19 , 20133 Milano , Italy . Email:
Chem Sci. 2019 Jan 4;10(9):2750-2757. doi: 10.1039/c8sc04126a. eCollection 2019 Mar 7.
Impressive spin-related effects are observed in cyclic voltammetry (CV) experiments performed under an applied magnetic field on a non-ferromagnetic electrode modified with a thin electroactive oligothiophene film, either "inherently chiral" or featuring chiral pendants with stereogenic centres. When flipping the magnet's north/south orientation, the CV peaks of two achiral, chemically reversible Fe(iii)/Fe(ii) redox couples in aqueous or organic solution undergo impressive potential shifts (up to nearly 0.5 V depending on protocol conditions), specularly by changing the film's ()- or ()-configuration. The magnitude of the potential shift decreases upon increasing both the polymer film thickness and the distance between the permanent magnet and the electrode surface. Such unprecedented spin-related redox potential modulation, obtained in the absence of a magnetic electrode acting as a spin injector, provides striking evidence (as well as an attractive evaluation criterion) of the spin selectivity properties of chiral thin films.
在施加磁场的条件下，对用薄的电活性低聚噻吩薄膜修饰的非铁磁电极进行循环伏安法（CV）实验时，观察到了令人印象深刻的自旋相关效应。该薄膜要么是“固有手性”的，要么具有带有立体中心的手性侧链。当翻转磁体的南北方向时，在水溶液或有机溶液中，两个非手性的、化学可逆的Fe(III)/Fe(II)氧化还原对的CV峰经历了令人印象深刻的电位偏移（根据实验方案条件，高达近0.5V），具体表现为通过改变薄膜的（）-或（）-构型而产生镜面反射式的变化。随着聚合物薄膜厚度以及永磁体与电极表面之间距离的增加，电位偏移的幅度会减小。在没有充当自旋注入器的磁性电极的情况下获得的这种前所未有的自旋相关氧化还原电位调制，为手性薄膜的自旋选择性特性提供了有力证据（以及一个有吸引力的评估标准）。
