在可切换的三联苯三醌桥联 Ni 配合物中，电子和自旋离域。

Electronic and spin delocalization in a switchable trinuclear triphenylene trisemiquinone bridged Ni complex.

机构信息

Institut de Chimie Moléculaire et des Matériaux d'Orsay, Université Paris-Sud, CNRS, Université Paris-Saclay, 91405 Orsay cedex, France.

Institut des Matériaux Poreux de Paris, UMR 8004 CNRS, École Normale Supérieure, Ecole Supérieure de Physique et de Chimie Industrielles de Paris, PSL University, 75005 Paris, France.

出版信息

Chem Commun (Camb). 2019 Oct 10;55(82):12336-12339. doi: 10.1039/c9cc05183j.

DOI:10.1039/c9cc05183j

PMID:31556434

Abstract

A trinuclear triphenylene trisemiquinone complex containing paramagnetic NiII is obtained under ambient conditions from the reaction of deprotonated tricatecholate hexahydroxytriphenylene (H6HHTP) with NiII capped with a trispyrazolyl borate tridentate ligand. The magnetic and EPR data are consistent with delocalization of the electronic spin over the three NiII species. The two-electron reduced complex shows an EPR spectrum corresponding to a S = 1/2 species due to a large antiferromagnetic coupling between the radical and only one of the NiII ions highlighting the localization of the electronic spin. No EPR signal is observed for the one- and three-electron reduced species consistent with the closed shell of the bridging ligand.

摘要

在环境条件下，通过将六羟基三苯并[g,p,q]苝（H6HHTP）去质子化与 NiII 反应，得到了一种包含顺磁性 NiII 的三核三联苯三-semiquinone 配合物，NiII 被三吡唑硼酸三齿配体封闭。磁性和 EPR 数据与电子自旋在三个 NiII 物种上的离域一致。由于自由基和 NiII 离子之一之间的强反铁磁耦合，两电子还原配合物显示出对应于 S = 1/2 物种的 EPR 谱，突出了电子自旋的局域化。对于一电子和三电子还原物种，没有观察到 EPR 信号，这与桥联配体的闭合壳层一致。