Aromatic hydrocarbons have many appealing fuel properties, such as high energy density and favorable autoignition behavior; however, they also have large propensities to form soot particles. We have shown that oxygenated aromatics can have much lower sooting tendencies than analogous regular hydrocarbons, but this behavior depends on the position of the oxygen atom. For example, 1-phenylethanol (1PE) has a measured yield sooting index (YSI) of 142, which is much lower (i.e., better) than ethylbenzene (YSI = 216), but 2-phenylethanol (2PE) has a YSI (207) that is similar to ethylbenzene. In a new paper accepted for the Proceedings of the Combustion Institute (), we use flow reactor experiments and quantum chemistry calculations to identify the chemical mechanisms for this difference. This work began as a Senior Project in Chemistry for Brian Beekley, who is a co-author of the paper. It was conducted in collaboration with Seonah Kim’s group at the National Renewable Energy Laboratory and Yuan Xuan’s group at Penn State.