Figure indicates that the largest deviations from sphericity occur with the evolution of the A systems, which contain organic fractions composed of only FAs. A1 and A3 specifically show the largest changes in symmetry, corresponding to the most dramatic changes in the 𝜅 2 parameter. We provide MD snapshots from the 500 ns timepoint for replicates A1 and A2 to illustrate. A1 evolves into an ellipsoidal shape within the first 100 ns of simulation time. A2 initially approaches and hovers around 𝜙 = 1000 before falling to 𝜙 = 500 at 200 ns, which corresponds to a more spherical and symmetric structure than A1 and more closely resembles the shape of the other systems. The more dramatic evolutions in particle shape appear to correspond to the higher FA content relative to the other systems. FAs, particularly protonated FAs, have high hydrophobicity and favor formation of highly ordered structures on a rapid timescale. This self-assembly has been explored experimentally on medium and long chain FAs in aqueous solutions. Once the surface saturates with a monolayer, FAs aggregate in bulk, forming micelles and lamellar vesicles of tunable size based on fatty acid chain length, temperature, pH, and salt concentration. 109-119 Indeed, vesicle formation within intact supermicron sea spray has been observed previously by Patterson et al. via cryogenic transmission electron microscopy. However, submicron aerosols, shown by our simulations, do not have sufficient volume for micelle or vesicle formation. Rather, the excess lipids-those not occupying space at the surface-aggregate into amorphous oil droplets that either adsorb to the monolayer or are freely suspended in the aqueous phase. The aggregates that form in the present simulations often take the form of bilayers and/or lipid agglomerates. For A1 and A3, the aggregate is a bilayer that bisects the aerosol to form an ellipsoidal shape; in A2, the aggregates are double bilayers that adhere to either side of the particle, maintaining the observed spherical shape (Figure ).