Abstract

Herein, we investigate the non-covalent interactions between aromatic compounds and a spirocycle-bearing imidazolidinedithione
molecule 3ʹ-aminofluorene-9-spiro-5ʹ-imidazolidine-2ʹ,4ʹ-dithione Host Material (HM). HM and planar aromatic solvent
molecules, such as benzene, pyrrole, and thiophene, form molecular compounds with a composition ratio of 2:1 through NH∙∙∙π
interactions. These compounds exhibit weak emission in the λmax range of 515–544 nm, which were estimated from the sum of the
squares of the differences between the electronegativities of the bonded atoms comprising the guest molecule structures without
employing quantum calculations. Moreover, a linear correlation between the desorption temperature and NH∙∙∙π interactions is
determined from the heats of formation of HM, guest molecules, and corresponding molecular compounds.