Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA and Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
J Chem Phys. 2019 Sep 21;151(11):114303. doi: 10.1063/1.5115169.
Bimetallic platinum complexes have interesting luminescent properties and feature long-lasting vibrational coherence and ultrafast intersystem crossing (ISC) after photoexcitation. Ultrafast triplet formation is driven by very strong spin-orbit coupling in these platinum (II) systems, where relativistic theoretical approaches beyond first-order perturbation theory are desirable. Using a fully variational relativistic theoretical method recently developed by the authors, we investigate the origins of ultrafast ISC in the [Pt(ppy) (μ-Bupz)] complex (ppy = phenylpyridine, pz = pyrazolate). Spin-orbit coupling values, evaluated along a Born-Oppenheimer molecular dynamics trajectory, are used to propagate electronic populations in time. Using this technique, we estimate ultrafast ISC rates of 15-134 fs in this species for the possible ISC pathways into the three low-lying triplet states.
双金属铂配合物具有有趣的发光性质，在光激发后具有持久的振动相干性和超快系间窜越（ISC）。超快三重态的形成是由这些铂（II）体系中的强自旋轨道耦合驱动的，其中需要超越一阶微扰理论的相对论理论方法。利用作者最近开发的完全变分相对论理论方法，我们研究了[Pt(ppy)(μ-Bupz)]配合物（ppy=苯基吡啶，pz=吡唑酸盐）中超快 ISC 的起源。自旋轨道耦合值沿 Born-Oppenheimer 分子动力学轨迹进行评估，用于随时间传播电子密度。使用该技术，我们估计该物种中可能的 ISC 途径进入三个低能三重态的超快 ISC 速率为 15-134 fs。
