Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
J Phys Chem Lett. 2022 Apr 7;13(13):3039-3046. doi: 10.1021/acs.jpclett.2c00207. Epub 2022 Mar 29.
Intersystem crossing (ISC), a vital component of the electronic and nuclear transitions that compose photophysics, has been successfully simulated in light elements and transition metal complexes. Derived from the -dependent spin-orbit coupling (SOC), ISC is expected to be of greater importance in heavier elements, but few attempts have been made at the simulation of ISC in lanthanides or actinides. In this work, we explore several of the challenges that will need to be overcome in order to treat ISC in late-row elements, including the loss of spin as a good quantum number, the need to include SOC variationally via two- or four-component electronic structure, and the high density of states present in late-row complexes. Density functional theory (DFT) calculations are used to illustrate several of these effects, while a model Hamiltonian is used to illustrate the importance of momentum rescaling in surface hopping simulations of strongly coupled states.
体系间窜越（ISC）是构成光物理的电子和核跃迁的重要组成部分，已成功在轻元素和过渡金属配合物中进行了模拟。ISC 源于与轨道角动量相关的自旋轨道耦合（SOC），预计在较重元素中更为重要，但在镧系或锕系元素中对 ISC 的模拟尝试很少。在这项工作中，我们探索了为了在后期元素中处理 ISC 需要克服的几个挑战，包括自旋作为好量子数的丧失，需要通过双分量或四分量电子结构变分来包含 SOC，以及后期元素中存在的高密度状态。密度泛函理论（DFT）计算用于说明其中的一些效应，而模型哈密顿量用于说明在强耦合态的表面跳跃模拟中动量重新缩放的重要性。
