Interactions of oxygen with polynuclear aromatic hydrocarbons (PAH) can occur both in the flame and during oxidation of soot atmospherically. Past experimental measurements of PAH in soot samples collected either immediately after combustion, from the atmosphere, or in a flame show a variety of oxygen moieties within the PAH structures. This study investigated the electronic structure of oxygen-containing PAH to gain insight into their interaction with light both to better interpret spectroscopic measurements and to recognize the role of oxygen-containing PAH in atmospheric radiative forcing. Our research has shown that oxygen in ethers and hydroxyl moieties on PAH showed little change to the HOMO-LUMO gap (HLG), whereas ketones and aldehydes show a HLG decrease of 0.5 eV. The effect is enhanced when more than one ketone is present on a PAH molecule and further enhanced in subsequent dehydrogenation to a quinone-like structure. The presence of an oxygen-containing PAH with a ketone functional group in a dimer and trimer will substantially lower the HLG of the PAH stack. This may have a significant effect in the interaction of atmospheric soot with solar radiation.

氧与多核芳香烃（PAH）的相互作用既可以在火焰中发生，也可以在大气中烟灰的氧化过程中发生。燃烧后立即从大气中或在火焰中收集的烟灰样品中过去对PAH进行的实验测量表明，PAH结构中存在多种氧部分。这项研究调查了含氧多环芳烃的电子结构，以了解它们与光的相互作用，以便更好地解释光谱测量结果，并认识到含氧多环芳烃在大气辐射强迫中的作用。我们的研究表明，PAH上的醚和羟基部分中的氧对HOMO-LUMO间隙（HLG）的变化很小，而酮和醛的HLG降低了0.5 eV。当PAH分子上存在一个以上的酮时，效果会增强，并在随后的脱氢成醌样结构中进一步增强。二聚体和三聚体中具有酮官能团的含氧PAH的存在将大大降低PAH叠层的HLG。这可能对大气烟灰与太阳辐射的相互作用产生重大影响。