Electronic properties of hydrogen bond networks

ELECTRONIC PROPERTIES OF HYDROGEN BOND NETWORKS IMPLICATIONS FOR SOLVENT EFFECTS IN POLAR LIQUIDS... 

STRUCTURE OF THE HYDROGEN BOND NETWORK AND ELECTRONIC PROPERTIES OF WATER... 

Electronic Properties Effects of the Surrounding. The proton affinity of the zinc-bound water molecule is a key property for the enzymatic mechanism. The acidity of the zinc bound water is the result of a subtle fine tuning via hydrogen-bonded networks and electrostatic environment effects. This quantity can thus serve as a sensitive indicator of differences in the electronic structure that will have a critical influence on the enzymatic reaction. As a first attempt to quantify the effect of the electrostatic environment and the varying size of the cluster model we have therefore calculated the proton affinities for the different models. 

The Fe and Mn SODs demonstrate clearly the dramatic effects of electronic OSC over active site properties. Differences between these two sites arise purely due to the hydrogen-bonding networks influencing the acidity of the axial solvent ligand. These variations in OSC are sufficient to tune Em across a large potential window in sites with essentially identical inner-sphere coordination environments. 

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