Gutman donor number

One of them is Gutmann s donor number, DN, (Gutman and Vychera 1966) defined as the negative of the standard molar heat of reaction (expressed in kcal mol 1, 1 cal = 4.184 J) of the solvent with antimony pentachloride to give the 1 1 complex, when both are in dilute solution in the inert diluent 1,2-dichloroethane. This quantity needs to be determined calorimetrically, as was done for a considerable number of solvents at that time (Gutman and Vychera 1966). There are several problems with the DN scale. One is the fact that calorimetric equipment... 

The donor number (DN) is defined as the negative AH value for the solvation of SbCls by a donating solvent in 1,2-dichloroethane solution Gutman, V. The Donor-Acceptor Approach to Molecular Interactions, Plenum Press New York, 1978, Chapter 2. 

Gutman chose the reaction enthalpy of solvent with the reference aeeeptor (antimony pentachloride) to quantify Lewis-donor properties. The donor number, DN, is a dimensionless parameter obtained from negative values of reaction enthalpy. The data obtained from electrochemical and NMR studies were combined into one scale in whieh data... 

Figure 10.85. Molar sorption of sulfur dioxide by polymeric membranes vs. their Gutman s donor number. [Data from Semenova S 1 Smirnov S I, J. Membrane Sci., 168, Nos.1-2, 13th March 2000, p.167-73.]...

The solvent donor number, first defined by Gutman [4] and abbreviated to DN, is a system specific, but quantitative measure of the ability of a substance to act as an electron pair donor. In its original form it is defined as the negative of the heat of reaction for the formation of the 1 1 adduct between the test substance and antimony pentachloride, measured in 1,2-dichloroethane as solvent (equation 12.2). 

The redox reactions of (TPP)CrCl04, (TPP)CrCl04(L) and [(TPP)Cr(L)2]+ were also investigated and correlations between Ei/2 for reduction of (TPP)CrCl04 and the Gutman solvent donor number [154], as well as between 1/2 for reduction of (TPP)CrCl04 or (TPP)Cr and the solvent dielectric constant, were also examined [98]. 

Acidic/Basic Lewis acidity/basicity determines the solvent s abihty to demate or accept a pair of electrons to form a coordinate bond with solute and/or between solvent molecules. A scale for this acid/base pre ierty was proposed by Gutman (DN and AN -donor and acceptor number, reflectively) based on caleuimetric determination. The complete proton transfer reaction with femnatiem of protonated ions is determined by proton affinity, gas phase acidity, acid or base dissociation constants. Both concepts differ in terms of net chemicsd reactiem. 

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