General Design Rules for Bimetallic Platinum(II) Complexes
General Design Rules for Bimetallic Platinum(II) Complexes
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DOI：
10.1021/acs.jpca.1c05044
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发表时间：
2021-10-26
影响因子：
2.9
通讯作者：
Li, Xiaosong
中科院分区：
文献类型：
--
作者：
Mills, Alexis W.;Valentine, Andrew J. S.;Li, Xiaosong
本文研究了一系列铂（II）配合物的几何结构和电子结构。通过桥连配体结构调节Pt-Pt距离被发现决定了最低能量电子跃迁的性质，其定位于分子的一半或在整个分子中离域。通过减少铂原子之间的间隔，最低能量的电子跃迁将由金属-金属-配体电荷转移跃迁主导。相反，通过增加铂原子之间的距离，最低的电子跃迁将主要是局部金属到配体的电荷转移或配体中心的性质。此外，环化配体被观察到具有显着的稳定效果的三重激发态的共轭增加，所产生的几何重新取向和增加的电子离域的配体。三重态能量的这种稳定化已经显示出改变激发态势能景观以及激发态轨迹。
A series of platinum(II) bimetallic complexes were studied to investigate the effects of ligands on both the geometric and electronic structure. Modulating the Pt-Pt distance through the bridging ligand architecture was found to dictate the nature of the lowest energy electronic transitions, localized in one-half of the molecule or delocalized across the entire molecule. By reducing the separation between the platinum atoms, the lowest energy electronic transitions will be dominated by the metal-metal-to-ligand charge transfer transition. Conversely, by increasing the distance between the platinum atoms, the lowest electronic transition will be largely localized metal-to-ligand charge transfer or ligand centered in nature. Additionally, the cyclometalating ligands were observed to have a noticeable stabilizing effect on the triplet excited states as the conjugation increased, arising from geometric reorientation and increased electron delocalization of the ligands. Such stabilization of the triplet state energy has been shown to alter the excited state potential energy landscape as well as the excited state trajectory.