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This quantity can be calculated as a sum over molecular fragments by the method of Meylan and Howard or by Rekker's method. This quantity can be measured using a namesake form of "centrifugal chromatography." The potency, as measured by the pIC50 [P-I-C-fifty], is plotted against this quantity on a LiPE [lye-pee] plot. The logarithm of 1 over the concentration that produces a standard response was related to the log of this quantity by Corwin Hansch, who thus developed the first quantitative structure-activity relationship." In column chromatography, the ratio of the volumes of the stationary and mobile phases times this quantity equals the capacity factor. This quantity, which is correlated with lipophilicity, is typically reported with respect to some reference system, such as cyclohexane and water, or octanol and water. For 10 points, name this quantity which determines the efficiency of a liquid-liquid extraction.
This quantity can be calculated as a sum over molecular fragments by the method of Meylan and Howard or by Rekker's method.
partition coefficient [or distribution coefficient; or "log P"; accept answers indicating "the logarithm of the partition coefficient"; prompt on "K" or "equilibrium constant"]