Ligand-Structure-Dependent Coherent Vibrational Wavepacket Dynamics in Pyrazolate-Bridged Pt(II) Dimers
Ligand-Structure-Dependent Coherent Vibrational Wavepacket Dynamics in Pyrazolate-Bridged Pt(II) Dimers
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吡唑酯桥 Pt(II) 二聚体中配体结构依赖性相干振动波包动力学
DOI：
10.1021/acs.jpcc.2c02256
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Chen, Lin X.
中科院分区：
文献类型：
--
作者：
Kim, Tae Wu;Kim, Pyosang;Mills, Alexis W.;Chakraborty, Arnab;Kromer, Sarah;Valentine, Andrew J.;Castellano, Felix N.;Li, Xiaosong;Chen, Lin X.
过渡金属双金属配合物由于其在太阳能转换和光子学应用中的广泛功能而受到越来越多的关注。在双金属铂（Pt）络合物中，Pt中心部分和配体中心部分之间的电子通信已被证明对于定义它们经历局部配体中心（LC）/金属至配体电荷转移（MLCT）跃迁或离域金属至配体电荷转移（MMLCT）跃迁的激发态动力学轨迹至关重要。激发态系间交叉（ISC）轨迹的分支是通过改变不同状态的相对能量的结构因素来调制的。在这项研究中，我们调查的相关性的结构因素影响的激发态轨迹。随着飞秒宽带瞬态吸收（fs-BBTA）光谱的使用，超快动力学在激发态的两个选择Pt（II）二聚体已映射出使用其相干振动波包签名在相应的瞬态吸收光谱。为了研究Pt（II）二聚体的配体部分如何影响激发态动力学和相干振动波包行为，我们对通式为[Pt（tBu 2 Pz）（N^C）]2[tBu 2 Pz是3，5-二叔丁基吡唑; N^C是7，8-苯并喹啉（bzq，1）或1-苯基异喹啉（piq，2）]的两种吡唑桥联的Pt（II）二聚体进行了比较研究。我们发现，光激发到1和2的低能吸收带，分别诱导形成的1 MMLCT态的超快ISC进行，导致受激发射猝灭和退相干的振动波包运动。在这项研究中得到的结果表明，无论是能量和结构刚性的芳香环化配体在1和2可以显着影响的动力学沿着激发态轨迹的相干振荡的退相为特征。集体的结果提供了直接的证据，如何配体结构改变电子动力学沿着激发态轨迹与ISC过程，提供洞察使用配体设计，以引导光化学过程。
Bimetallic transition metal complexes have gained increasing attention because of their versatile functions in solar energy conversion and photonics applications arising from intermetal electronic coupling. In bimetallic platinum (Pt) complexes, electronic communication between the Pt-centered and ligand-centered moieties has been shown to be critical for defining their excited-state dynamic trajectories undergoing either localized ligand-centered (LC)/metal-to-ligand charge-transfer (MLCT) transitions or delocalized metal–metal-to-ligand charge-transfer (MMLCT) transitions. The branching of the excited-state intersystem crossing (ISC) trajectories is modulated through structural factors that alter the relative energies of the different states. In this study, we investigated the correlation of the structural factors influencing the excited-state trajectories. With the use of femtosecond broad-band transient absorption (fs-BBTA) spectroscopy, ultrafast dynamics in the excited state of two select Pt(II) dimers have been mapped out using their coherent vibrational wavepacket signatures in the corresponding transient absorption spectra. To examine how the ligand moieties of the Pt(II) dimers influence excited-state dynamics and the coherent vibrational wavepacket behavior, we carried out comparative studies on two pyrazolate-bridged Pt(II) dimers of the general formula [Pt(tBu2Pz)(N^C)]2[tBu2Pz is 3,5-di-tert-butylpyrazole; N^C is 7,8-benzoquinoline (bzq,1) or 1-phenylisoquinoline (piq,2)]. We found that photoexcitation into the low-energy absorption bands of1and2, respectively, induces the formation of1MMLCT states from which ultrafast ISC proceeds, resulting in stimulated emission quenching and decoherence of the vibrational wavepacket motions. The results obtained in this study suggest that both the energetics and the structural rigidity of the aromatic cyclometalating ligands in1and2can significantly influence the dynamics along the excited-state trajectory characterized by dephasing of the coherent oscillations. The collective results provide direct evidence of how ligand structure alters electronic dynamics along excited-state trajectories associated with ISC processes, providing insight into using ligand design to steer photochemical processes.
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影响因子：
2.9
作者：
Liebel, M.;Schnedermann, C.;Kukura, P.
通讯作者：
Kukura, P.
可以通过分子结构修饰来调节激发态电子相干性吗？
DOI：
10.1021/acs.jpca.6b12099
发表时间：
2017
期刊：
The journal of physical chemistry. A
影响因子：
--
作者：
D. Lingerfelt;Patrick J. Lestrange;Joseph J Radler;Samantha E Brown;Pyosang Kim;F. Castellano;Lin X. Chen;Xiaosong Li
通讯作者：
Xiaosong Li
影响因子：
2.9
作者：
Cho, Sung;Mara, Michael W.;Chen, Lin X.
通讯作者：
Chen, Lin X.
影响因子：
4.6
作者：
Barzegar-Kiadehi, S. Reza;Haghighi, Mohsen Golbon;Notash, Behrouz
通讯作者：
Notash, Behrouz
影响因子：
16.6
作者：
Gaynor, James D.;Sandwisch, Jason;Khalil, Munira
通讯作者：
Khalil, Munira