Wang Wenjun, Xu Xuesong, Yang Zijiang
School of Science, Dalian Maritime University, Dalian 116026, China.
School of Science, Dalian Maritime University, Dalian 116026, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Jul 5;275:121179. doi: 10.1016/j.saa.2022.121179. Epub 2022 Mar 23.
Photoinduced charge transfer (CT) mechanisms of two Donor-π-Donor-π-Acceptor conjugates composed of ferrocene (Fc), zinc-porphyrin (ZnP), and fullerene (C) linked by phenylene-acetylene/acetylene during the one- (OPA) and the two-photon absorption (TPA) processes are analyzed theoretically based on the density functional theory calculations and visualization methods to study the effects of linkage between the two donors on the excitation characteristics. The change of bridge affects the efficiency of superexchange CT from Fc to ZnP in the OPA process. The one-photon excitations are dominated by local transitions of ZnP and Fc, and there is almost no efficient CT from the donors to the acceptor for both the two researched structures. In contrast, the advantage of superexchange CT from ZnP to C becomes much larger than the other transition forms during the TPA process when the linkage between ZnP and Fc is changed from acetylene to phenylene-acetylene. This linkage effect in TPA would have great significance in designing novel optoelectronic devices.
基于密度泛函理论计算和可视化方法，对由二茂铁（Fc）、锌卟啉（ZnP）和富勒烯（C）通过亚苯基 - 乙炔/乙炔连接而成的两种供体 - π - 供体 - π - 受体共轭物在单光子吸收（OPA）和双光子吸收（TPA）过程中的光诱导电荷转移（CT）机制进行了理论分析，以研究两个供体之间的连接对激发特性的影响。桥的变化会影响OPA过程中从Fc到ZnP的超交换CT效率。单光子激发主要由ZnP和Fc的局域跃迁主导，对于所研究的两种结构，从供体到受体几乎没有有效的CT。相比之下，当ZnP和Fc之间的连接从乙炔变为亚苯基 - 乙炔时，在TPA过程中从ZnP到C的超交换CT优势比其他跃迁形式大得多。TPA中的这种连接效应在设计新型光电器件方面具有重要意义。
