利用电子振动跃迁计算预测实验激发态吸收光谱：其在π共轭分子中的实际应用
Prediction of experimental excited-state absorption spectra by using vibronic transition calculations: Its practical application to a π-conjugated molecule
浏览论文内容
中文总结 AI 辅助
研究旨在解决激发态吸收光谱理论预测难题，结合电子振动跃迁计算与常规DFT、TDDFT计算，以薁为模型验证，为分子低激发态跃迁产生的ESA谱带归属提供实用框架，无需激发态跃迁矩确定绝对强度。
中文摘要 AI 辅助
准确的激发态吸收（ESA）光谱理论预测仍具有挑战性。尽管ESA光谱计算方法取得了很大进展，但它们在瞬态吸收和光致吸收光谱解释中的实际应用仍然有限。在本研究中，我们提出了一种实用方法，通过将电子振动跃迁计算与标准量子化学软件包中的常规密度泛函理论（DFT）和含时密度泛函理论（TDDFT）计算相结合来计算分子ESA光谱。以薁为模型系统，我们证明该方法成功再现了实验ESA光谱中观察到的电子振动特征和谱带位置。因此，该方法为分子低激发态之间跃迁产生的ESA谱带归属提供了实用框架。该方法直接从这些标准计算中给出了归属ESA谱带所需的值，无需确定绝对强度的激发态到激发态跃迁矩。
英文摘要
Accurate theoretical prediction of excited-state absorption (ESA) spectra remains challenging. Although considerable progress has been made in computational methods for ESA spectroscopy, their practical application to the interpretation of transient absorption and photoinduced absorption spectra is still limited. In this study, we present a practical approach for calculating molecular ESA spectra by combining vibronic transition calculations with routine density functional theory (DFT) and time-dependent DFT (TDDFT) calculations available in standard quantum chemistry packages. Using azulene as a model system, we demonstrate that the proposed method successfully reproduces the vibronic features and band positions observed in the experimental ESA spectrum. This approach therefore provides a practical framework for assigning ESA bands arising from transitions between low-lying excited states of molecules. The method delivers the vibronic band shapes and peak positions that are needed to assign ESA bands directly from these standard calculations, without requiring the excited-state-to-excited-state transition moments that determine absolute intensities.
