Resolution factor and separation factor:

The resolution factor and the separation factor are not the same. They are related by the expression

R = N ½ (α - 1)α/4

R = resolution factor, N = number of plates and α = separation factor. R, the ratio of retention time measured at the peaks of elution bands, does not itself represent the effectiveness of separation because it does not tell the width of the peak. If R = 1, a good separation seems to be possible but with α = 1 no separation seems to be feasible however large the number of plates may be.