Unveiling the atomistic and electronic structure of NiII-NO adduct in a MOF-based catalyst by EPR spectroscopy and quantum chemical modelling

Kavipriya Thangavel; Paolo Cleto Bruzzese; Matthias Mendt; Andrea Folli; Katharina Knippen; Dirk Volkmer; Damien M Murphy; Andreas Pöppl

doi:10.1039/d3cp01449e

Unveiling the atomistic and electronic structure of Ni^II-NO adduct in a MOF-based catalyst by EPR spectroscopy and quantum chemical modelling

Phys Chem Chem Phys. 2023 Jun 15;25(23):15702-15714. doi: 10.1039/d3cp01449e.

Authors

Kavipriya Thangavel^{1

2}, Paolo Cleto Bruzzese^{1

3}, Matthias Mendt¹, Andrea Folli², Katharina Knippen⁴, Dirk Volkmer⁴, Damien M Murphy², Andreas Pöppl¹

Affiliations

¹ Felix Bloch Institute for Solid State Physics, Leipzig University, Linnéstraße 5, 04103 Leipzig, Germany. poeppl@physik.uni-leipzig.de.
² School of Chemistry, Main building, Cardiff University, CF10 3AT, Cardiff, UK.
³ Department of Chemistry and NIS Centre of Excellence, University of Turin, via Giuria 9, 10125 Torino, Italy.
⁴ Institute of Physics, Chair of Solid State and Materials Chemistry, University of Augsburg, Universitätstraße 1, D-86159 Augsburg, Germany.

PMID: 37259848
DOI: 10.1039/d3cp01449e

Abstract

The nature of the chemical bonding between NO and open-shell Ni^II ions docked in a metal-organic framework is fully characterized by EPR spectroscopy and computational methods. High-frequency EPR experiments reveal the presence of unsaturated Ni^II ions displaying five-fold coordination. Upon NO adsorption, in conjunction with advanced EPR methodologies and DFT/CASSCF modelling, the covalency of the metal-NO and metal-framework bonds is directly quantified. This enables unravelling the complex electronic structure of Ni^II-NO species and retrieving their microscopic structure.