The photochemical pathways of acetanilide and paracetamol were investigated using the XMS‐CASPT2 quantum chemical method and the cc‐pVDZ (correlation consistent polarized valence double‐) basis set. In both compounds, the bright state is the second excited state, designated as a La) state. Through a detailed exploration of the potential energy profile and the conical intersection structure between the La) and ground states, we gained a better understanding of how cleavage might occur in both molecules upon photoexcitation. Other potential relaxation mechanisms, including crossings with the dark and La) states, are also discussed in detail.

中文翻译：

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扑热息痛和乙酰苯胺的激发态弛豫机制


使用 XMS-CASPT2 量子化学方法和 cc-pVDZ （相关一致极化价双-） 基集研究乙酰苯胺和扑热息痛的光化学途径。在这两种化合物中，亮态是第二激发态，指定为 La） 态。通过详细探索势能分布以及 La） 和基态之间的圆锥形交会结构，我们更好地了解了光激发时两个分子如何发生裂解。还详细讨论了其他可能的弛豫机制，包括与暗态和 La） 态的交叉。