A new series of Schiff bases synthesized from the condensation of substituted aldehydes and 1,3-diaminopropane in ethanol (2:1) were studied and their electronic absorption spectra in organic solvents of varying polarities had been investigated. The electronic absorption spectra, IR bands and 1H NMR signals of the most important functional groups were assigned and discussed in relation to molecular structure. The structural and molecular orbital calculations of the compounds were investigated theoretically by performing density functional theory (DFT) to access reliable results to the experimental values where the calculated results showed good agreement with the experimental values. The calculated HOMO and LUMO energies showed that intramolecular charge transfer occurs within the molecules.