Theoretical study of water clusters: octamer

Twenty nine structures of the (H2O)8 are examined. Calculations were carried out with a Hartree-Fock wavefunction using the 6-311G∗, and 6-311G∗∗ basis sets. SCF force constants were calculated with both basis sets and the information used to generate thermodynamic data. The enthalpies, entropies, and free energies of the twenty nine structures are presented and compared. It is shown that entropy scales linearly with spatial extent of the cluster size. This allows calculation of entropy per volume of water cluster. Infrared and Raman spectra of three structures, cube, di-ring and ring, are also presented.