The Avobenzone (AVOB) molecule is very photoactive and undergoes irreversible degradation upon irradiation. We studied its valence and core-level (C1s and O1s) photoionisation and subsequent photofragmentation with photoelectron spectroscopy and photoelectron–photoion–photoion coincidence (PEPIPICO) spectroscopy. AVOB is one of the largest molecules studied with this technique. The results show that the AVOB molecule dissociates into an extensive range of fragments by different pathways with little element or site-selectivity. The coincident maps were used to determine selected fragment separation sequences by analysing the slopes of patterns from ion pairs after the core ionisation. Charge delocalisation over the benzene rings and their relative stability favor fragmentation by cleavage of the bridge between them.

阿伏苯宗（AVOB）分子具有很高的光活性，并且在照射后会发生不可逆的降解。我们研究了其价和核心级（C1小号和O1小号）通过光电子能谱和光电子-光子-光子重合（PEPIPICO）光谱进行电离和随后的光碎裂。AVOB是使用此技术研究的最大分子之一。结果表明，AVOB分子通过不同的途径以很少的元素或位点选择性解离成大范围的片段。通过分析核心电离后离子对的模式斜率，可将重合图用于确定选定的片段分离序列。苯环上的电荷离域及其相对稳定性有利于通过裂解它们之间的桥来使其断裂。