Energies of the local minima (isomers) for , , , , and . Energies are given as in units of Kelvin relative to the GM for each individual cluster. The highest-energy level shown has .
Schematic of the local minima (isomers) and connecting transition states of the potential-energy surface for . Local minima are designated by a solid line; transition states by a dashed line. Transition states between minima are shown only if they have energy less than . If more than one transition state links two minima, only the lowest in energy is shown. Minima and transition states are joined by a dashed line if they are connected. The geometries of the isomers (local minima) are also shown in the figure. The energies of the local minima are given in Table II.
Disconnectivity graphs for , , , and . The vertical scales are arbitrary. The numbers on the graph refer to the isomer labels of Fig. 2.
Heat-capacity curves as a function of for (a) , , and and (c) , , and . (b) for repeated together with (multiplied by ten for clarity).
Probability of occupation of the minima of the system as a function of temperature. In the top panel each of the minima is shown individually. In the middle panel the data for isomers 1–3 are shown separately, together with the sum of probabilities in isomers 4–8. The label “square planar core” refers to the geometry of the core in local minimum 1 and “tetrahedral core” refers to the geometry of the core in isomers 2 and 3. In the lower panel 1–3 are summed and 4–8 are shown separately.
(Lower) Mean temperature for as a function of total energy for MD trajectories initiated in isomer 1 (filled circles) and isomer 2 (open circles). (Upper) Isomerization rate constant as a function of mean temperature for MD trajectories initiated in isomer 1 (the GM; filled circles) and isomer 2 (the first “excited state,” open circles).
Bond fluctuation parameter as a function of temperature for . Data are for a single trajectory. Open symbols are the results obtained by initiating the trajectory in the local minimum No. 2; filled symbols are the results obtained by initiating the trajectory in the GM, No. 1. Circles are the results obtained by sampling the trajectory every ; squares are the results obtained by sampling every .
Lennard-Jones parameters for Ar–Ar, Xe–Xe, and Ar–Xe interactions.
Local minima on the PES. The total potential energy is found from Eq. (1) relative to the atoms at infinity. Also given in the first column are the symmetry of the cluster and that of the core. (Local minima—or isomers—6 and 8 have structures which are not similar to stationary points of the isolated .) The third column gives the potential energy relative to the global minimum No. 1. Energies are given in units of Kelvin.
Saddle points on the surface. The eight lowest energy saddle points are listed in order of increasing potential energy. In the second column, the total potential energy is given. In the third column, the energy relative to the global minimum is given. (As in Table II and elsewhere in this paper, energies are given in Kelvin.) In the fourth column listed the two local minima connected by the saddle point.
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