Energetic and fragmentation stability of water clusters (H2O)n, n = 2–30

Ab initio calculations have been performed to study the structural trend, energetic stability, and fragmentation behavior of water clusters (H2O)2–30. We show that as size increases, the cluster structures evolve from a mono-ring motif to multi-ring and ring-stacking motifs, and then to stuffed cage structures. We also show that losing water molecules one-by-one is the most favorable fragmentation channel with a dissociation energy of ∼11.53 kcal/mol. Small water clusters such as water dimer, trimer, and tetramer, can also be observed in the fragmentation products since they often appear in the second best fragmentation channel.