Rotational coherence spectroscopy has been applied in a structural study of anthracene-(Ar)(n) (n = 0-3), 9,10 dichloroanthracene-(Ar)(n) (n = 0,1), and tetracene-Ar. Geometries consistent with the experimental results have been determined for each of the species. These geometries are compared with previous structural predictions from minimum energy calculations and vibronic frequency shift rules and are considered in the light of other known aromatic-(Ar)(n) structures.