A @S05757@ defined by: \[Sp = 1 - \frac{M}{M\left(\text{hexadecane}\right)}\] derived from the Gibbs energy of transfer (\(\Delta _{\text{t}}G^{\,\unicode{x26ac}}\)) of a series of solutes from water to numerous aqueous-organic mixtures and to pure solvents: \[\Delta _{\text{t}}G^{\,\unicode{x26ac}}\left(\text{to solvent}\right) = M\ R_{\text{T}}+D\] where \(R_{\text{T}}\) is a solute parameter, and \(M\) and \(D\) characterize the solvent. The \(M\) values are used to define a solvent solvophobic effect so that \(Sp\) values are scaled from unity (water) to zero (hexadecane).