Examination of protonation-induced dinitrogen splitting by in situe XAFS spectroscopy

DOI: 10.1021/acs.inorgchem.0c02134

Authors: Josh Abbenseth (University of Göttingen) , Jean-pierre H. Oudsen (University of Amsterdam) , Bas Venderbosch (University of Amsterdam) , Serhiy Demeshko (Georg- August-Universitaẗ Göttingen) , Markus Finger (Georg- August-Universitaẗ Göttingen) , Christian Herwig (Humboldt Universitaẗ zu Berlin) , Christian Würtele (Humboldt Universitaẗ zu Berlin) , Max C. Holthausen (Goethe-Universitaẗ) , Christian Limberg (Humboldt Universitaẗ zu Berlin) , Moniek Tromp (University of Groningen) , Sven Schneider (Georg- August-Universitaẗ Göttingen)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Inorganic Chemistry

State: Published (Approved)
Published: September 2020
Diamond Proposal Number(s): 22432

Abstract: The splitting of dinitrogen into nitride complexes emerged as a key reaction for nitrogen fixation strategies at ambient conditions. However, the impact of auxiliary ligands or accessible spin states on the thermodynamics and kinetics of N–N cleavage is yet to be examined in detail. We recently reported N–N bond splitting of a {Mo(μ2:η1:η1-N2)Mo}-complex upon protonation of the diphosphinoamide auxiliary ligands. The reactivity was associated with a low-spin to high-spin transition that was induced by the protonation reaction in the coordination periphery, mainly based on computational results. Here, this proposal is evaluated by an XAS study of a series of linearly N2 bridged Mo pincer complexes. Structural characterization of the transient protonation product by EXAFS spectroscopy confirms the proposed spin transition prior to N–N bond cleavage.

Journal Keywords: Redox reactions; Reaction mechanisms; Extended X-ray absorption fine structure; Physical and chemical processes; Quantum mechanics

Subject Areas: Chemistry


Instruments: B18-Core EXAFS