A huge congrats to Morgan on her newly published manuscript in J. Chem. Phys.! This paper explains how to model the absorbance spectra of organic molecular aggregates that are a mixture of H- and J-aggregates, and shows the clever method she came up with to fit her simulated spectra to those measured experimentally. This allows her to use simple benchtop in situ absorbance measurements to tell her something about the evolving structure and composition during the aggregation of of organic molecules into thin films. Thanks to Morgan our lab has gone from having no idea how to simulate absorbance spectra to being able to do it for complex aggregate mixtures. Great job, Morgan!!