H2O-HCI complex

Table 1 Previously reported geometrical parameters for the H2O-HCI complex. Distances are reported in A and angles in degrees...

A potential energy curve was also computed for different values of the roci distance in the H2O-HCI complex, with HCl approaching H2O along the C2v axis. At each roci distance, optimal SCF geometry was determined and used in the subsequent SCF-MI and MCSCF-MI calculations. 

The potential energy curve (Figure 4) relative to the approach of HCl to NH3 has the same characteristics observed for the H2O-HCI complex, with the MCSCF-Ml curve essentially parallel to the SCF-Ml curve. 

Analogous results are obtained for this system, see Table 12. Also in this case the SCF-MI and MCSCF-MI results show a greater stability for what concerns the basis set if compared with the SCF method. The difference between the force constants relative to asymptotic and equilibrium geometries (AK) is positive. The AK for the NH3-HCI complex is greater than that of the H2O-HCI complex. 

Fig. 5. Potential energy curve relative to the interconversion between ionic and covalent structure for the H2O-HCI. complex (H2O + HCl + Cl ). doH represents the distance between the water molecule...

Table 8 SCF, SCF-MI and MCSCF-MI calculated binding energies relative to the equilibrium geometries (reported in Table 7) for the H2O-HCI complex. All the values are in kcaUmol...

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