Term: peak resolution, \(R_{\text{s}}\)
https://doi.org/10.1351/goldbook.P04465

Definition:
The separation of two peaks in terms of their average peak width at base (t R2 > t R1): \[R_{\text{s}}=\frac{t_{\text{R2}}\,-\,t_{\text{R1}}}{\frac{w_{\text{b1}}\,+\,w_{\text{b2}}}{2}}=\frac{2\ (t_{\text{R2}}- t_{\text{R1}})}{w_{\text{b1}}\,+\,w_{\text{b2}}}\] In the case of two adjacent peaks it may be assumed that w b1 ≈ w b2, and thus, the width of the second peak may be substituted for the average value: \[R_{\text{s}}\approx \frac{t_{\text{R2}}\,-\,t_{\text{R1}}}{w_{\text{b2}}}\]

Source: Orange Book, 2nd ed., p. 108 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'peak resolution, \(R_{\text{s}}\)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04465

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