Azobenzene is a prototypical molecular photoswitch, widely used to trigger a variety of transformations at different length scales. In systems like self-assembled monolayers or micelles azobenzene chromophores may interact with each other, which gives rise to emergence of exciton states. Here, using first-principles calculations, we investigate how conformational disorder (induced, e.g., by thermal fluctuations) affects localization of these states, on an example of an H-type azobenzene

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... . We find that conformational disorder leads to (partial) exciton localization on a single-geometry level, whereas ensemble-averaging results in a delocalized picture. The ππ* and nπ* excitons at high and low temperatures are discussed.