Abstract:
:An unprecedented, spontaneous, and complete cleavage of the triple bond of N2 in the thermal reaction of 15N2 with Ta214N+ was observed experimentally by Fourier transform ion cyclotron resonance mass spectrometry; mechanistic aspects of the degenerate ligand exchange were addressed by high-level quantum chemical calculations. The "hidden" dis- and reassembly of N2, mediated by Ta2N+, constitutes a full catalytic cycle. A frontier orbital analysis reveals that the scission of the N2 triple bond is essentially governed by the donation of d-electrons from the 2 metal centers into antibonding π*-orbitals of N2 and by the concurrent migration of electrons from bonding π- and σ-orbitals of N2 into empty d-orbitals of the metals. This work may contribute to a rational design of catalysts in order to reduce the still enormous energy demand required for an artificial dinitrogen activation.
journal_name
Proc Natl Acad Sci U S Aauthors
Geng C,Li J,Weiske T,Schwarz Hdoi
10.1073/pnas.1913664116subject
Has Abstractpub_date
2019-10-22 00:00:00pages
21416-21420issue
43eissn
0027-8424issn
1091-6490pii
1913664116journal_volume
116pub_type
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