Looking at the overall interactions within these close solvation shells of the complex, we can divide up the interactions in two main categories: (1) complex-water, and (2) waterwater. Up until now, we have been focusing on the first type of interactions. Next, in order to investigate the relationship between these two types of interactions, we consider each of the complex-water clusters as two supermolecular entities, i.e., the complex and its solvation shell. Thus, V , the total interaction energy introduced in equation 1, can be broken down into the interaction energy between the complex and its solvation shell, V CS , and the interaction energy of the n water molecules excluding the complex, V WW . The following definitions are used to define these interactions: