A diagrammatic representation of data on scattering from large particles, corresponding to the equation: \[\frac{Kc}{\Delta R (\theta)} = \frac{1}{\bar{M}_{\rm{w}} P(\theta)} + 2\ A_{2}c + \ldots\] and used for the simultaneous evaluation of the mass average molar mass, \(\bar{M}_{\rm{w}}\), the second virial coefficient of the chemical potential, \(A_{2}\), and (usually) the z-average radius of gyration, \(< s^{2} > _{\rm{z}}^{\frac{1}{2}}\); \(c\) is the mass concentration of the solute, \(\Delta R(\theta)\) the excess Rayleigh ratio, and \(P (\theta )\) the particle scattering function that comprises (usually) the z-average radius of gyration. \(K\) depends on the solute, the temperature and the type of radiation employed. Several modifications of the Zimm plot are in frequent use; the most common one uses the excess scattering instead of the excess Rayleigh ratio.