Water solubility: a critique of the solvatochromic approach

The reasoning and some of the assumptions behind the solvatochromic approach to water solubility are evaluated, particularly in relation to its claims. It is shown that the contribution of the pi term is uncertain, and that it can be dropped from the correlation without substantially affecting the degree of fit. The solvatochromic method is compared with the long-standing relationship between solubility and the octanol-water partition coefficient, and it is demonstrated that the latter offers a far superior route to solubility estimation.