Gas-apolane partition coefficients (L(87)) of 157 nonpolar and polar organic solutes, spanning a wide range of functional groups, dipolarities, and hydrogen-bonding capabilities, are measured by open tubular capillary gas chromatography at 40 °C. The experimental values compare well (R(2) = 0.999) with literature values of log L(87) from packed-column gas chromatography. The log L(87) values are also compared with gas-hexadecane partition coefficients (log L(16)) at 25 °C. A strong linear relationship exists between log L(87) and log L(16) for all solutes (R(2) = 0.994), as well as for chemically relevant subsets of the data. Therefore, unknown L(16) values at 25 °C can be predicted from the corresponding L(87) values, which can be measured on open-tubular or packed columns at higher temperatures, due to the low volatility of apolane. Predicted values of L(16) would be extremely useful, since log L(16) is often the major explanatory parameter in many linear solvation energy relationships.

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The standard free energy of solution of Me,Sn(g) in 36 pure solvents has been determined by gas-chromatographic head-space analysis. Calorimetrically determined enthalpies of solution of liquid Me,Sn have been combined with the known enthalpy of vaporisation of Me,Sn to yield values of the enthalpy, and thence the entropy, of solution of Me,Sn(g) in 28 pure non-aqueous solvents. It is shown that values of AS: do not vary greatly with the non-aqueous solvent. Attempts have been made to calculate values of AGZ, A% and AS: for Me,Sn(g) in a number of solvents by use of SPT or SRMR calculations of cavity terms and Lennard-Jones or Kirkwood-Muller calculations of interaction terms. Similar calculations have been carried out for a range of non-polar, gaseous solutes in a few selected solvents.t This contrasts with the conclusions of de Ligny and van der VeenI8 who examined data on the solution of a large number of small solutes in non-aqueous solvents. They found that the AGZ values were described quite well, but that the AS: values could not be well reproduced. $ 1 cal = 4.184 J. C. B. Kretschner and R. Wiebe, solutes from ref. (6) unless shown otherwise. LJ and KM calculations.

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