Fig. 4. Views of the crystal structure of H·MAC·(PF6). (a) A view showing the stacked pair of MAC guests with part of the surrounding cage, emphasising the H-bonding interactions between inwardly-directed CH protons on the cage surface and the MAC guests: CH⋯O interactions with H⋯O distances of <3 Å are shown by green dotted lines. (b) A space-filling view of the cage looking onto one of the metal vertices, emphasising the binding of the hexafluorophosphate anions (green) in the surface portals. (c) The array of six hexafluorophosphate anions surrounding the two cavity-bound MAC molecules, with short (<3 Å) H⋯F contacts between MAC and [PF6]− anions arising from CH⋯F or NH⋯F interactions shown by green dotted lines.
