The density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were performed to get insights into the properties of PRODAN derivative in toluene at both ground as well as excited states. On the basis of molecular structure analysis, spectra comparisons and electron density studies, we confirm that the intermolecular hydrogen bond in PRODAN derivative-toluene complex is strengthened upon the photoexcitation. Frontier molecular orbitals exhibited the similar electron density distributions in HOMO and LUMO, suggesting that the PRODAN derivative 1a experiences the local excitations in toluene.