Figure 6.

Relative orientation of the two solutes used to form simultaneous hydrogen bonds with a solvent water-bridge. The solutes are shown as sticks, with oxygens colored red, hydrogens colored white, and the lonepair orbitals colored yellow. Note that lonepair orbitals were not explicitly included in the model of the water molecules, but are shown here to aid in understanding the hydrogen bonding geometry. A solvent water, distinguished by a magenta-colored oxygen, is also shown to indicate the concept of the intervening bridge when the solutes are at an appropriate separation. However, all solvent waters were allowed to move freely in the simulations.