THE STUDY OF REVERSED PHASES BY INVERSE GAS-CHROMATOGRAPHY

The surface properties of three silica-based reversed phases have been studied by inverse gas chromatography. Theoretical deduction indicate s that there is a linear relationship between the molar deformation po larisation of the test solute (P-D) and the dispersive interaction ene rgy between the solute and the C18 and non-bonded silica surfaces. The specific interaction energy between the solute molecule and the silic a surface (-Delta G(SP)) can be measured as the vertical distance betw een the solute experimental retention data point (RTl(n)V(N)) and the n-alkane RTl(n)V(N) vs P-D calibration line. From multiple regression analysis of -Delta G(SP) data with proton acceptor solubility paramete r delta(a) and orientation solubility parameter delta(o) as variants, two coefficients can be obtained related to the influence of the resid ual silanol groups and the trace metal impurities.