Using a 4hyphen;31G basis set for water and a four term wave function for the trapped electron (twosand twopfunctions), the energy of clusters as large as (H2O)minus;nwithn=8 are calculated. Large clusters (n7 or 8) might be thermally stable, but still appear to have higher energies than neutral clusters. The excitation energy of the excess electron increases rapidly as a function of cluster size. Most of the stability of the clusters is obtained with the second coordination layer. Convergence of the lsquo;lsquo;heat of solutionrsquo;rsquo; energy is quite slow as a function of the number of waters; the increases are about 7 kcal/mol per water in the second coordination shell and about 1ndash;2 kcal/mol for molecules in the third coordination shell. Sixfold coordination in the first coordination layer about the electron leads to a species slightly lower in energy than fourfold coordination. Spin density at the hydrogens in all cases is negative in these SCF calculations, contrary to the experimental results of Kevan in alkaline glasses.
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