School of Physics, Henan Normal University, Xinxiang 453007, China; Huangshi Key Laboratory of Photoelectric Technology and Materials, College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China.
School of Physics, Henan Normal University, Xinxiang 453007, China; Henan Key Laboratory of Infrared Materials & Spectrum Measures and Applications, Henan Normal University, Xinxiang 453007, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Jun 15;234:118200. doi: 10.1016/j.saa.2020.118200. Epub 2020 Feb 26.
Anthraquinone derivatives have been widely used as photocleavage agents and dyes. Here, photoinduced excited state intramolecular charge transfer (ICT) dynamics of 1-aminoanthraquinone in ethanol are studied by femtosecond transient absorption (fs-TA) spectroscopy and quantum chemical (QC) calculations. Four decay associated difference spectra and corresponding lifetime components were obtained by singular value decomposition and global fitting analysis from the fs-TA spectra. The QC calculations prove that the S state has obvious ICT character. Planar ICT (PICT) and twisted ICT (TICT) reaction coordinates are observed. On the PICT coordinate, vibrational relaxation (VR) and intersystem crossing (ISC) processes are observed. The ISC efficiency is dependent on excitation wavelength, which elucidates that T' state participates in the ISC process on a higher-level than the S' state. On the TICT coordinate, the TICT process is dependent on excitation wavelength, which elucidates a direct experimental evidence of an energy barrier in excited state TICT potential energy.
蒽醌衍生物被广泛用作光解试剂和染料。在这里，通过飞秒瞬态吸收（fs-TA）光谱和量子化学（QC）计算研究了 1-氨基蒽醌在乙醇中的光诱导激发态分子内电荷转移（ICT）动力学。通过奇异值分解和全局拟合分析，从 fs-TA 光谱中得到了四个衰减相关的差分光谱和相应的寿命分量。QC 计算证明 S 态具有明显的 ICT 特征。观察到平面 ICT（PICT）和扭曲 ICT（TICT）反应坐标。在 PICT 坐标上，观察到振动弛豫（VR）和系间窜越（ISC）过程。ISC 效率取决于激发波长，这表明 T'态比 S'态更高级地参与 ISC 过程。在 TICT 坐标上，TICT 过程取决于激发波长，这提供了激发态 TICT 势能中存在能量势垒的直接实验证据。
