Two-state Reaction Mechanism of the Synthesis of Ammonia in the N2/H2/Ru
Systems: A Theoretical Study
Abstract
Ru-based catalysts show high activity and stability to produce ammonia.
Herein, the two-state reaction mechanism of Ru catalyzes N2 and H2 to
synthesize NH3 are theoretical studied with the density functional
theory(DFT)UB3LYP methods. The spin-orbital coupling constant(Hsoc) and
intersystem crossing probability(Pisc) at minimum energy crossing
point(MECP) were calculated, respectively. its are:
Hsoc,MECP1=508.34cm-1,P2,MECP1ISC=0.85,MECP2:Hsoc,MECP2=269.21cm-1,
P2,MECP2ISC=0.27. Used energy span model to determined TOF-determining
transition state(TDTS) as 3TS2-3 and TOF-determining intermediate(TDI)
as 3IM9 of reaction.In addition, the charge decomposition analysis(CDA),
spin population analysis and frontier molecular orbital(FMO) theory were
used to analyzed reaction mechanism.