Molecular (Geometric and Electronic) Structure of Paramagnetic Centres

HYSCORE spectrum revealing a Ni(III)-H species, and a density function calculation for the paramagnetic centre

The interactions between a paramagnetic centre and the surrounding magnetic nuclei (i.e. 1H, 2H, 14N, 13C, 63,65Cu, etc.) allow the local geometric and electronic structure to be characterised.

Typical target for this type of study are organic radicals, catalytic materials and complexes, and active sites of metalloenzymes.

Electron-nuclear coupling up to ca. 10Å from the paramagnetic centre are measurable at the CAI with a combination of multi-frequency CW EPR and high-resolution pulse EPR techniques including HYSCORE, ENDOR and ELDOR spectroscopies. The interactions of interest are the nuclear Zeeman, Zero-field, hyperfine and nuclear quadrupole interactions. This experimental data can be combined with quantum chemical calculations, such DFT, to elucidate a structural model of the paramagnetic centre and interacting substrates and molecules.

CW EPR – continuous wave electron paramagnetic resonance spectroscopy
HYSCORE – hyperfine sublevel correlation
ENDOR – electron nuclear double resonance
ELDOR – electron double resonance