Additionally, excess uptake is directly sensitive to how the pore volume is determined (e.g. geometric pore volume, probe-occupiable pore volume, van der Waals volume, Connolly volume, and more) , which pores are accessible , and whether the pore volume can change as is the case with flexible MOFs/COFs . Net uptakes, shown in Equation , try to address these issues by measuring uptake with respect to the empty unit cell at the same pressure, thereby directly assessing whether the adsorbent improves overall storage capacity.