Computed Relative Populations of D2(22)-C84 Endohedrals with Encapsulated Monomeric and Dimeric Water

Abstract

Water monomer and dimer encapsulations into D2(22)-C84 fullerene are evaluated. The encapsulation energy is computed at the M06-2X/6-31++G∗∗ level, and it is found that the monomer and dimer storage in C84 yields an energy gain of 10.7 and 17.4 kcal mol-1, respectively. Encapsulation equilibrium constants are computed by using partition functions based on the M06-2X/6-31G∗∗ and M06-2X/6-31++G∗∗ molecular data. Under high-temperature/high-pressure conditions, similar to that for the encapsulation of rare gases in fullerenes, the computed (H2O)2@C84-to-H2O@C84 ratio is close to 1:2.