Factors Affecting the Magnitude of the Distribution Coefficient (K_d ):

The magnitude of (K_d) is determined by the relative affinity of the solute for the two phases. Those solutes interacting more strongly with the stationary phase will exhibit a high distribution coefficient and will be retained longer in the chromatographic system. Molecular interaction results from intermolecular forces of which there are three basic types. (a) Dispersion forces (b) Polar forces (c) Ionic forces

If the compound X has same affinity for both the phase, it gets distributed equally in both the phases but compound Y has differential affinity for two phases and accordingly gets distributed in stationary and mobile phase.

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