Prediction of ?OH-Initiated and ?NO3-Initiated Transformation Products of Polycyclic Aromatic Hydrocarbons by Electronic Structure Approaches

The abiotic reaction products of polycyclic aromatic radicals (center dot NO3) are nitro-, oxygen-, and hydroxyl-containing PAHs (NPAHs, OPAHs, and OHPAHs). Four methods of the highest occupied molecular orbital (HOMO), Fukui function (FF), dual descriptor (DD), and population of pi electrons (PP-pi) are selected to predict the chemical reactivity of PAHs attacked by center dot OH and center dot NO3 in this study. The predicted center dot OH-initiated and center dot NO3initiated transformation products are compared with the main PAH transformation products (PAH-TPs) observed in the laboratory. The results indicate that PP-pi and DD approaches fail to predict the transformation products of fused PAHs containing five-membered rings. By predicting the PAH-TPs of 13-14 out of the 15 parent PAHs accurately, HOMO and FF methods were shown to be suitable for predicting the transformation products formed from the abiotic reactions of fused PAHs with center dot OH and center dot NO3.

Automated summary

Four methods were used to predict the chemical reactivity of polycyclic aromatic hydrocarbons (PAHs) attacked by different radicals. The results showed that two of the methods were able to accurately predict the transformation products of PAHs, while the other two methods failed to predict the transformation products of fused PAHs containing five-membered rings.