0.505 Å. Guest A, however, when considered as the only guest in the pore, has a calculated ∆E strain of 8.26 kJ/mol: compared to configurations where both guests are present, the RMS deviation in atomic positions is small (0.166 Å), but causes an increase in ∆E strain of nearly 4 kJ/mol. While there are no observed direct guest-guest interactions in the experimental and optimised structure, the increase in intramolecular strain energy of guest A when guest B is present demonstrates the influence of dispersive forces between molecules in the pores even when no direct atom-atom interactions are observed.