Two‐Photon Solvatochromism II: Experimental and Theoretical Study of Solvent Effects on the Two‐Photon Absorption Spectrum of Reichardt's Dye. Issue 16 (17th September 2013)

• Record Type: Journal Article
• Authors: Wielgus, Małgorzata; Zaleśny, Robert; Murugan, N. Arul; Kongsted, Jacob; Ågren, Hans; Samoc, Marek; Bartkowiak, Wojciech
• Is Part Of: Chemphyschem. Volume 14:Issue 16(2013)
• Page Start: 3731
• Page End: 3739
• Publication Date: 2013-09-17
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201300695
• Languages: English
• ISSNs: 1439-4235

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>In this study, we report on the influence of solvent on the two‐photon absorption (2PA) spectra of Reichardt's dye (RD). The measurement of 2PA cross‐sections is performed for three solvents (chloroform, dimethyl formamide, and dimethyl sulfoxide) using the <italic>Z</italic>‐scan technique. The key finding of this study is the observation that the cross‐section, corresponding to the 2PA of the intramolecular charge‐transfer state, diminishes substantially upon increasing the solvent polarity. To unravel the solvent dependence of the 2PA cross‐section, the electronic structure of RD is determined using a hybrid quantum mechanics/molecular mechanics (QM/MM) approach, in which polarization between the solute and solvent is taken into account by using a self‐consistent scheme in the solvent polarization. The two‐state approximation proves to be adequate for the studied system, and allowed the observed solvent‐polarity‐induced decrease of the 2PA cross‐section to be related to the decrease of the transition moment and the increase in the excitation energy.</p> </abstract>