Table 1. Physical properties of the Good [1, 2, 3] buffers. The maximum distance between atomic centers of each buffer was measured from a 3-D model and used as an estimate of its molecular Stokes radius (a). The same was done for weak electrolytes with known diffusion coeficients (D). Linear regression of D vs 1/a for the weak electrolytes was used to predict the expected value of the Ds (E[D]) of the Good buffers. Atomic distances were measured using the Chem-3D plugin from CambridgeSoft Corporation (www.camsoft.com) in combination with 3-D data models of the compounds available from the online ChemFinder Database.