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Updated: May 30, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
The O-H stretching mode of a prototypical photoacid as a local dielectric probe
Mirabelle Prémont-Schwarz1, Dequan Xiao, Victor S Batista
1Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, D-12489 Berlin, Germany.
Abstract:
We investigate the OH stretch vibrational frequency shifts of a prototype photoacid, 2-naphthol (2N), when dissolved in solvents of low polarity. We combine femtosecond mid-infrared spectroscopy and a theoretical model based on the Pullin-van der Zwan-Hynes perturbative approach to explore vibrational solvatochromic effects in the ground S(0) and the first electronically excited (1)L(b) states. The model is parametrized using density functional theory (DFT), at the B3LYP/TZVP and TD-B3LYP/TZVP levels for the 2N chromophore in the S(0) and (1)L(b) states, respectively. From the agreement between experiment and theory we conclude that vibrational solvatochromic effects are dominated by the instantaneous dielectric response of the solvent, while time-dependent nuclear rearrangements are of secondary importance.
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