Theoretical studies of structures and stabilization energies of (H2O)26, (H2O)27 and (H2O)28 pentakaidecahedral clusters

The 26, 27 and 28 mer pentakaidecahedral water clusters were studied by applying the intermediate neglect of differential overlap self-consistent field restricted Hartree-Fock method (INDO SCF RHF) after parameterization for H and O atoms. The 27 and 28 mer clusters have one and two water molecules respectively within the cavity of the distorted pentakaidecahedral cage, and the H atoms on the surface are rearranged giving H3O2, H5O2, H5O3, and H7O3 species. The stabilization energy (SE)/monomer values for the most stable 26, 27 and 28 mer pentakaidecahedral clusters are 9.88, 10.58 and 10.98 kcal respectively with all the non H-bonding H atoms (NHB H) directed outward.