Volume of the stationary phase, which stays permanently within the column in counter-current chromatography.
Note: \(V_{\rm{s}}\) is one of the most important parameters that determines the peak resolution.
Source:
PAC, 2017, 90, 181. 'Terminology of separation methods (IUPAC Recommendations 2017)' on page 205 (https://doi.org/10.1515/pac-2017-0111)