summary of the calculated energetics for the various models (kcal/mol)a,b.

aRelative energies, with respect to the most stable prereactive complex, of the critical structures for studied models.bThe composition of each model: dissociative I [1 Mg2+|2 H2O|Asp457-H+|Asp477-H+], dissociative II [1 Mg2+|1 H2O], dissociative III [2 Mg2+|1 H2O| Asp477-H+], dissociative IV[1 Mg2+|1 H2O|Asp457-H+|Asp477-H+], dissociative V [1 Mg2+|2 H2O|Asp457-H+|Asp477-removed], associative I [1 Mg2+|2 H2O|Asp457-H+|Asp477-H+], associative II [2 Mg2+|1 H2O], associative III [2 Mg2+|4 H2O].cThe energies of associative I are respect to dissociative I. The composition of associative I and dissociative I are the same.