1 INTRODUCTION Metalloenzymes make up nearly 40% of all enzymes1, 2 and catalyze some of nature's most challenging reactions such as the reduction of nitrogen gas to ammonia,3 splitting of water,4 and the activation of CH bonds in rather inert species with high selectivity.5, 6 Computation plays a key role in assigning intermediates7, 8 in metalloenzyme catalytic cycles, probing the electronic structure of metallocofactors,9-11 and aiding in crystallographic refinement of metal centers in...
