Physical properties of some common organic solvents.  See definitions for parameters at the bottom of this page.  Experimental Chemistry I CH 362&362H.

Click here to get the solvent parameter chart that was shared in lecture

Definitions for Some Solvent Parameter:

α = hydrogen bond donating ability of the solvent (or electron pair accepting ability); HBD ranges from ~0-1

β = hydrogen bond acceptance ability of the solvent (or electron pair donating ability); HBA ranges from ~0-1

π = combination of polarity and polarizability of the solvent,  ranges from 0-1

ε= dielectric constant, a macroscopic property of the solvent as a continuous medium.

μ = dipole moment, units of debyes, a microscopic property of the individual molecule.

Y = log(k(test solvent)/k(80%EtOH/water)) for SN1 reaction of tert-butyl chloride at 25°C. A more polar solvent makes this reaction faster, and Y more positive.

 

Z = transition energy for the longest wavelength absorption band for the excitation of methyl N-ethyl-4-pyridinecarboxylate iodide in the particular solvent, units of kcal/mol.

 

 

 

ET = same as Z but with Dimroth-Reichardt betaine dye* in the particular solvent, units of kcal/mol.

 

For both Z and ET, the stabilization of the polar dye molecule vs. the nonpolar excited state leads to an increase in excitation energy in polar solvents.

 

Reference:  Y. Marcus, The Properties of Organic Liquids that are Relevant to their Use as Solvating Solvents, Chem. Soc. Rev. 22, 361 (1993)

*2,6-Diphenyl-4-(2,4,6-triphenyl-1-pyridinio)phenoxide

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02/16/15 ;