Bedogni Matteo, Di Maiolo Francesco
Department of Chemistry, Life Science and Environmental Sustainability, Università di Parma, 43124 Parma, Italy.
J Chem Theory Comput. 2024 Oct 8;20(19):8634-8643. doi: 10.1021/acs.jctc.4c00706. Epub 2024 Sep 12.
The discovery of singlet-triplet (ST) inversion in some π-conjugated triangle-shaped boron carbon nitrides is a remarkable breakthrough that defies Hund's first rule. Deeply rooted in strong electron-electron interactions, ST inversion has garnered significant interest due to its potential to revolutionize triplet harvesting in organic LEDs. Using the well-established Pariser-Parr-Pople model for correlated electrons in π-conjugated systems, we employ a combination of CISDT and restricted active space configuration interaction calculations to investigate the photophysics of several triangular boron carbon nitrides. Our findings reveal that ST inversion in these systems is primarily driven by a network of alternating electron-donor and electron-acceptor groups in the molecular rim, rather than by the triangular molecular structure itself.
在一些π共轭三角形硼碳氮化物中发现单重态-三重态（ST）反转是一项非凡的突破，它违背了洪德第一规则。ST反转深深植根于强烈的电子-电子相互作用，因其有可能彻底改变有机发光二极管中的三重态俘获而引起了极大关注。我们使用在π共轭系统中用于相关电子的成熟的巴黎-帕尔-波普尔模型，结合耦合簇单双激发（CISDT）和受限活性空间组态相互作用计算，来研究几种三角形硼碳氮化物的光物理性质。我们的研究结果表明，这些系统中的ST反转主要是由分子边缘交替的电子供体和电子受体基团网络驱动的，而不是由三角形分子结构本身驱动的。
