The inevitable broadening of peaks during the chromatographic process may make it difficult to discern two consecutive peaks in a chromatogram from each other. Such a situation will occur if the peaks overlap extensively. The ability to resolve two consecutive peaks is defined as the resolution and is given by;
The widths of the two closely eluting peaks are nearly equal. For quantitative work a clear separation of peaks is necessary. However it is not necessary to have a large separation between the peaks (overkill). The value of R for quantitative analysis need not be exceedingly large (what is the significance of R = 1.5?). Note that one can tell the presence of two peaks for smaller R but for quantitative work smaller R values are unsatisfactory. Of the examples given below, for R = 0.50 the peaks do not resolve all.
These graphs (consecutive peaks of equal sizes) were generated from a Quattro-pro worksheet; in C:\C380\wks2.wq2.
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