Stationary absorption, fluorescence excitation and fluorescence spectra for 9 (10H)- acridinone, 9 (10-methyl)-acridinone, 2-methyl-9 (10-methyl)-acridinone, 2-nitro-9 (10- methyl)-acridinone, 9 (10-ethyl)-acridinone and 9 (10-phenyl)-acridinone dissolved in 1, 4- dioxane, methyl alcohol or acetonitrile, as well as the available spectral characteristics reported by others were compared with those predicted theoretically at the semi-empirical ...