The initial motifs for all three amines were extracted from publicly available CIFs . Based on the size and nature of the amine, different possible configurations in the pore were hypothesized. For N,N'-dimethylethylenediamine, we simply rotated the diamine by 90 degrees to point along the crystallographic c-axis. This decision is discussed in Section III A. For norspermine (N,N'-bis(3-aminopropyl)-1,3-diaminopropane), the general flexibility of the molecule gives rise to different configurations of the gaseous phase. We chose two: one was the linear configuration, which is what one would get if they downloaded the molecular coordinates on ChemSpider 45 , and the other was the 'S-shaped' configuration, which is observed in the bound state in the pore . For spermine (N,N'bis(3-aminopropyl)-1,3-diaminobutane), we studied the sole gaseous configuration to be the mostly linear one, which again is close to what is observed in the experimental structure . These different structures allow 8 unique motifs.