Evaluating the Solvent Stark Effect from Temperature‐Dependent Solvatochromic Shifts of Anthracene

Abstract

The solvent Stark effect on the spectral shifts of anthracene is studied with temperature‐dependent solvatochromic measurements. The Stark contribution ΔvStark to the absorption shift Δvp in polar solvents is measured to be ΔvStark=(53±35) cm−1, in reasonable agreement with dielectric continuum theory estimate of 28 cm−1, whereas the major shift Δvp∼300 cm−1 presumably originates from the solute quadrupole. We pay attention to the accurate correction of Δvp for the nonpolar contribution that is crucial when the shifts are modest in magnitude.

Electronic States of Tris(bipyridine) Ruthenium(II) Complexes in Neat Solid Films Investigated by Electroabsorption Spectroscopy

“…The solvatochromism of a RBY complex in liquid solvents is rather weak, and the solvent shifts of the MLCT absorption band [ 16 ] are similar in size to the higher-energy ( 1 B 2u ) singlet state for the nonpolar anthracene molecule [ 17 ] but rather quite small when compared to typical molecular charge-transfer bands [ 2 ]. Although the observed solvent dependence of the MLCT absorption band by Kober et al [ 16 ] was ascribed to the polar excited state with an electron localized on a single ligand and a permanent dipole moment of 14 D, this interpretation was later criticized for several reasons [ 2 , 15 , 18 ].…”