Indicates the total porosity of the column. The total porosity includes both the interparticle space and the intraparticle space.
The total porosity is calculated from the following equation:
where
εT = total porosity
Ve = volume of eluent the column that is between the stationary phase particles (not in them)
Vi = volume of eluent within the stationary phase particles
V = total volume in the empty column
εe = interparticle porosity
εi = intraparticle porosity
The total porosity of a column is usually around 0.65