The molecular geometries of hydrogen cluster ions, H3+(H2)n (n = 3-16), were investigated by using the classical Monte Carlo and annealing method. The two-body potential functions were obtained by fitting the results of ab initio MP4(SDTQ) calculations. Molecular structure and stability are mainly determined by an ionic interaction between H3+ and H2. The H2-H2 interaction forces H2 molecules to stay away from each other but seems to have little effect upon the structure and stability of clusters in the vicinity of the equilibrium structure. The n dependency of the binding energy (-ΔEn-1,n) is in good agreement with the experimental trend in -ΔHn-1,n known for n ≤ 9. Magic numbers in the stabilization energy have been found at n = 3, 6, 9, 12, and 15, where optimized molecular structures are closed shells with 3-fold symmetry and have one to five layers of (H2)3 solvation shells over the H3+ core.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry