Determination of ground and excited state dipole moments of amino-benzimidazole by solvatochromic shift methods and theoretical calculations
Solvatochromic behavior of 2-aminobenzimidazole (2-AB) has been studied in different solvents at room temperature. The observation of the bathochromic shift in the absorption and fluorescence spectra of molecules indicates a strong interaction with solvents in the excited state. The difference in the excited-state (?e) and the ground-state (?g) dipole moments has been estimated by using the theory of solvatochromism from Bakhshiev, Bilot–Kawski, and Dimroth–Reichardt equations. Higher values of dipolemoment have been observed for excited state compared to the corresponding ground state values indicating an intramolecular charge-transfer (ICT).
Then in order to carry out a theoretical investigation, the values of dipole moments were calculated in the gas phase with TDDFT/B3LYP. Based on these results, we propose a solvation model consistent with theoretical and experimental results wherein we showed the specific interactions between solvent molecules and aminobenzimidazole at the excited state.
Auteur(s) : D.D. Thiaré, A. Khonté, A. Diop, L. Cissé, A. Coly, A. Tine, F. Delattre
Pages : 640-646
Année de publication : 2015
Revue : Journal of Molecular Liquids
N° de volume : 211
Type : Article
Mise en ligne par : COLY Atanasse