FIG. 5 .FIG. 6 .
56Electron hopping integral t(d) as a function of the distance d between two H ions. The hydrogen hopping integral decreases rapidly with increasing distance between the two H-ions. The equilibrium separation between the two nearest Htet's, and between neighboring Htet and Hoct are 5.29 a.u.and 4.58 a.u., respectively. The solid line shown here is fitted to the three **data** points. A cubic cell with the center of H − 2 as the origin is shown. Total charges of ions enclosed in the cell are neutral. Charges in unit of e on an edge, surface and corner are counted as a quarter, half and eighth of the original charges respectively. Only a few examples are given in the figure. Dotted lines are guides to the eyes.
