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Updated: Nov 21, 2025

Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Solvatochromy and symmetry breaking in two quadrupolar oligophenylenevinylenes
N A Nemkovich1, H Detert2, A N Sobchuk3
1Institute of Organic Chemistry, J. Gutenberg-University of Mainz, Duesbergweg 10-14, 55099 Mainz, Germany; B.I. Stepanov Institute of Physics, NASB, Independence Ave. 68, 220072 Minsk, Belarus.
Abstract:
Electrooptical absorption measurements (EOAM), solvatochromic dependences and quantum chemical simulations testify to large dipole moments change of two quadrupolar oligophenylenevinylenes upon transition to Franck-Condon excited state μeFC. The values of the dipole moments μg and μeFC are in the range [(4.2 - 4.9)1030] C m and (30.8 - 47.0)1030C m, respectively. The relations of dipole moments in the ground and excited states determined by EOAM correlate well with results obtained via the solvatochromic method. Calculations carried out by density functional theory (DFT) show that optimized configuration of the ground state of these molecules is not planar. The results from all methods applied unequivocally show the structural symmetry breaking in the studied compounds.
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