Modeling Water Clusters on Cationic Carbonaceous Seeds

Abstract

The Dang-Chang many-body polarizable potential has been used to model the interaction between water molecules and a cationic carbonaceous molecule X(+), with X = C(60) (buckminsterfullerene), C(24)H(12) (coronene), or C(20)H(10) (corannulene). The most stable structures of (H(2)O)(n)X(+), located with the basin-hopping method, consist of a water cluster next to the carbon cation but often deviate from those obtained for pure water clusters. The accuracy of the intermolecular potential is checked by performing dedicated high-level electronic structure calculations using the B97-1 density functional. Finally, some thermodynamical and dynamical manifestations of the nonwetting behavior are discussed.

Adsorption of molecular hydrogen on coronene with a new potential energy surface

“…Global minima were obtained using the BH 62 or Monte Carlo (MC) minimization 63 method, successfully employed before for both neutral 62,64,65 and charged atomic and molecular clusters [66][67][68][69][70][71] , along with many other applications. 72 This technique is a stochastic method that involves perturbation followed by minimization at each step.…”

Phase changes of the water hexamer and octamer in the gas phase and adsorbed on polycyclic aromatic hydrocarbons

“…Nevertheless, its explanation can also be found in the energy level diagram of the water clusters in the gas phase and adsorbed on the PAHs, as the gap between the most stable cubic structure and the energetically higher isomers is strongly reduced when the cluster is adsorbed on the PAH surface, as shown in ref 87 and reported in Table 1. 66 This observation was also used to interpret a phase change shift toward lower temperatures when the water octamer is adsorbed on C + 60 . 66 This observation was also used to interpret a phase change shift toward lower temperatures when the water octamer is adsorbed on C + 60 .…”

“…[61][62][63][64][65][66][67] Indeed, it is a convenient quantity that allows for an easy identification of the temperature at which a phase change occurs. [61][62][63][64][65][66][67] Indeed, it is a convenient quantity that allows for an easy identification of the temperature at which a phase change occurs.…”

“…[61][62][63]66,67 In particular, Pedulla and Jordan rationalized the influence of the choice of the FF on the simulated heat capacity curves of the water hexamer and octamer. Typically, millions of single-point energy calculations are required, which is a bottleneck for ab initio potentials.…”

“…[61][62][63]66,67 In particular, Pedulla and Jordan rationalized the influence of the choice of the FF on the simulated heat capacity curves of the water hexamer and octamer. 66,67 As for water clusters, FF potentials were also used in those investigations. 76 They observed a variation of ⇠100 K and ⇠200 K in the phase change temperature of (H 2 O) 6 20 cluster and found a variation of ⇠20 K of the phase change temperature for the different tested FF.…”