title: Theoretical studies of N2 reduction to ammonia in Fe(dmpe)2N2.
abstract: Electronic structure calculations using density functional theory were performed on potential intermediates in the reaction of Fe(dmpe)(2)N(2) (dmpe = 1,2-bis(dimethylphosphino)ethane) with protons. Three mechanisms were investigated and compared, and the possibility of a two-electron reduction by a sacrificial Fe(dmpe)(2)N(2) complex was considered in each mechanism. A Chatt-like mechanism, involving the stepwise addition of protons to the terminal nitrogen, was found to be the least favorable. A second pathway involving dimerization of the Fe(dmpe)(2)N(2) complex, followed by the stepwise addition of protons leading to hydrazine, was found to be energetically favorable; however many of the dimeric intermediates prefer to dissociate into monomers. A third mechanism proceeding through diazene and hydrazine intermediates, formed by alternating protonation of each nitrogen atom, was found to be the most energetically favorable.
authors.affiliation: Computational Science Institute, 5294 University of Oregon, 1600 Millrace Drive Suite 105, Eugene, Oregon 97403, USA.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Yelle
authors.forename: Justin L
authors.initials: JL
authors.lastname: Crossland
authors.forename: Nathaniel K
authors.initials: NK
authors.lastname: Szymczak
authors.forename: David R
authors.initials: DR
authors.lastname: Tyler