Quantum-mechanical studies of water and aqueous ionic solutions

Quantum-mechanical studies of water and aqueous (ionic) solutions 

The free gas-phase HjO molecule has been the subject of extremely accurate quantum-mechanical calculations of both its ground state, excited 

All values are given in atomic units. The experimental H2O equilibrium geometry is used. 

This raises a question often important in simulation studies to what extent can a system such as M + (H20) be described in terms of and H2O-H2O pair interactions Clearly, the most desirable situation for 

Metal (M) Total energy (a.u.) Hydration energy (kj mol ) Metal-water distance (A)  

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