Accordingly, 40 simulations were performed using the fully deprotonated, apo Octacid4 that was surrounded by 8 neutralizing sodium cations and 150 xylenes. Here, the number of xylenes was arbitrarily chosen. Gratifyingly, all 40 14,251.6-ns simulations with the octa-anionic, apo Octacid4 with 150 xylenes captured the self-assembly of Octacid4 with xylene at 298 K. Additional simulations were performed using one of the five variations: (1) replacing the fully deprotonated, apo Octacid4 with the octa-anionic Octacid4 possessing 5 water molecules inside the cavity, (2) increasing the number of xylenes to 250, (3) replacing 150 xylenes with 150 dioxanes, (4) replacing 150 xylenes with 150 naphthalenes, or (5) changing the Berendsen thermostat to the Langevin thermostat. These simulations all captured the self-assembly event. By contrast, no complexation was observed under the same conditions if the octa-anionic, apo Octacid4 surrounded by 8 sodium cations was replaced with the neutral, apo Octacid4 without any cations. All simulations described hereafter used the octaanionic, apo Octacid4 surrounded with 8 sodium cations, 150 guests, and the Berendsen thermostat.