For each voxel, we wish to estimate the probability that it is occupied by an adsorbate in the GC ensemble. During the simulation, at the end of each production cycle, we take a "snapshot" by, for each adsorbate in the system, incrementing by one the count associated with the voxel to which it belongs. At the end of the simulation, the adsorbate counts in each voxel serve as a D histogram for the adsorbates over the simulation volume; normalizing by the total number of snapshots taken gives an estimation of the spatial probability density of the adsorbates in the MOF during the simulation of the GC ensemble. We write this grid to a .cube file and visualize the density for . .