Solvent-Induced shifts of the

Table I) is due to the so1ute-s01vent interactions that result in solvent induced shifts of the singlet-singlet excitation energies readily observable in solution absorption s p ec t r a (J 2). As expressed in... 

From the Q model, the solvent-induced shift of the equilibrium free energy gap Fq = U + AFs,i is given by the following relation ... 

A small selection of other strongly solvatochromic fluorophores, recommended as solvent polarity probes because of their large solvent-induced shifts of the long-wavelength emission band, is given in Scheme 1 further examples can be found in references [10, 16, 112, 486],... 

The application of eight different reaction-field models to the solvent-induced shift of the carbonyl IR absorption band of 2-butanone, determined in 27 non-HBD solvents, has shown that in this group of solvents the dipolarity and polarizability are the dominating solvent properties responsible for the observed band shift (Avc o = —16 cm for -hexane —> sulfolane) [499]. Among the various reaction-field functions tested, a two-parameter equation with the Kirkwood-Bauer-Magat function /(fir) and the cross function f si,n ) was the most successful one. 

SOLVENT INDUCED SHIFTS OF THE EXCITATION ENERGIES OF LINEAR POLYENYNES AND ir-ELECTRON STATE ORDERING... 

The solvent induced shift of the conformational equilibrium was confirmed, in toluene at -20°C a ratio of 3 and 0.75 was calculated for 2ae and 2at respectively while in ethylacetate these values decrease to 0.8 and 0.4. 

Sok, S., Willow, S. Y., Zahariev, R, Gordon, M. S. (2011). Solvent-Induced Shift of the Lowest Singlet fl fl Charge-Transfer Excited State of P-Nitroaniline in Water An Application of the TDDFT/EFPl Method,/. Phys. Chem. A, 115,9801-9809. 

The IT Scale. Proposed in 1977 by the present authors (33h) this scale is based on the solvent-induced shifts of the frequency maxima of the x - ir transitions of seven indicators 4-nitroanisole (VII), N,N-diethyl-3-nitro-aniline (VIII), 4-methoxy-/S-nitrostyrene (IX), l-ethyl-4-nitrobenzene (X), N-methyI-2-nitro-p-toluidine (XI), N,N-diethyl-4-nitroaniline (XII) and 4-di-methylaminobenzophenone (XIII). 

S Akimoto, O Kajimoto. Solvent-induced shift of the Raman spectra in supercritical fluids. Chem Phys Lett 209 263, 1993. 

Note that the two-level model also allows a simple estimation of molecular P values through spectroscopic measurement. Spectra recorded in solvents of different polarity can be used to determine the transition moments and dipole difference from absorption strength and solvent-induced shift of the absorption maximum. 

Solvatochromism Solvent-induced shift of the UVA is/NIR absorption band (and change in intensity) of light-absorbing solute. A hypsochromic (blue) shift with increasing solvent polarity is called negative solvatochromism, a corresponding bathochromic (red) shift is called positive solvatochromism. 

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