To overcome this limitation, Yuan et al. manually blocked the cage windows using a "virtual plane", obtaining a volume of 7,026 Å 3 using the one-probe rolling probe method (probe radius of 1.4 Å) using VOIDOO (Figure ). Utilizing C3, with a 2.0 Å grid spacing, we obtained a volume of 6,800 Å 3 , which is comparable to the volume obtained by Yuan and coworkers (Figure ).