Determining Excited-State Structures and Photophysical Properties in Phenylphosphine Rhenium(I) Diimine Biscarbonyl Complexes Using Time-Resolved Infrared and X-ray Absorption Spectroscopies
Determining Excited-State Structures and Photophysical Properties in Phenylphosphine Rhenium(I) Diimine Biscarbonyl Complexes Using Time-Resolved Infrared and X-ray Absorption Spectroscopies
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使用时间分辨红外和 X 射线吸收光谱测定苯基膦铼 (I) 二亚胺双羰基配合物的激发态结构和光物理性质
DOI：
10.1021/acs.inorgchem.1c00146
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发表时间：
2021
影响因子：
4.6
通讯作者：
Ken Onda
中科院分区：
文献类型：
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作者：
Yuushi Shimoda;Kiyoshi Miyata;Masataka Funaki;Takumi Ehara;Tatsuki Morimoto;Shunsuke Nozawa;Shin-ichi Adachi;Osamu Ishitani;Ken Onda
本文研究了顺，反-[Re（DMB）（CO）2（PPh_2Et）_2]~+（Et（2，2））和顺，反-[Re（DMB）（CO）_2（PPh_3）_2]~+（（3，3））两种双亚胺配合物在乙腈溶液中的物理化学性质（dmb = 4，4 ′-二甲基-2，2 ′-联吡啶，Ph =苯基，Et =乙基）的时间分辨红外光谱组合法，时间分辨的扩展X射线吸收精细结构和量子化学计算。这些配合物之间的差异是膦配体中苯基的数量，这仅间接影响中心Re（I）。尽管有这种微小的差异，复合物表现出很大的差异，在发射波长和激发态寿命。在光激发下，两种配合物中Re-P键长和P-Re-P键角均发生了显著变化，而苯基仅在（3，3）中发生了大幅度的旋转.与此相反，有小的变化，在苯基基团上的电荷分布时，Re到DMB的电荷转移发生在光激发。我们的结论是，苯基和二亚胺的空间效应的不稳定性导致较小的最低激发三重态（T1）在（3，3）的斯托克斯位移。基态和激发态之间的大的结构变化导致T1 in（3，3）的较长寿命。
We have explored the structural factors on the photophysical properties in two rhenium(I) diimine complexes in acetonitrile solution,cis,trans-[Re(dmb)(CO)2(PPh2Et)2]+(Et(2,2)) andcis,trans-[Re(dmb)(CO)2(PPh3)2]+((3,3)) (dmb = 4,4′-dimethyl-2,2′-bipyridine, Ph = phenyl, Et = ethyl) using the combination method of time-resolved infrared spectroscopy, time-resolved extended X-ray absorption fine structure, and quantum chemical calculations. The difference between these complexes is the number of phenyl groups in the phosphine ligand, and this only indirectly affects the central Re(I). Despite this minor difference, the complexes exhibit large differences in emission wavelength and excited-state lifetime. Upon photoexcitation, the bond length of Re–P and angle of P–Re–P are significantly changed in both complexes, while the phenyl groups are largely rotated by ∼20° only in (3,3). In contrast, there is little change in charge distribution on the phenyl groups when Re to dmb charge transfer occurs upon photoexcitation. We concluded that the instability from steric effects of phenyl groups and diimine leads to a smaller Stokes shift of the lowest excited triplet state (T1) in (3,3). The large structural change between the ground and excited states causes the longer lifetime of T1in (3,3).