Two-photon solvatochromism. I. Solvent effects on two-photon absorption cross section of 4-dimethylamino-4′-nitrostilbene (DANS)

This Letter reports a systematic study of solvent effect on two-photon absorption (2PA) spectra of a model chromophore, 4-dimethylamino-4′-nitrostilbene (DANS). The two-photon solvatochromic behavior of DANS was investigated in selected solvents using the Z-scan measurement technique. The obtained results demonstrate that the examined molecule possesses slightly different 2PA response in solvents of different polarity. A decrease in the two-photon absorption strength is observed when the solvent is changed from chloroform and dichloromethane to the more polar dimethyl sulfoxide.

80Highlights► Solvents of different polarity tune the two-photon absorption spectra of DANS. ► A decrease in 2PA absorption strength parameter is observed for more polar solvent (DMSO). ► Maximum of the 2PA response of DANS is reached for the solvents of intermediate polarity. ► Presented observations support recent theoretical predictions.