Thesis

Research in biochemistry and catalytic chemistry
relies on electron spin resonance
(ESR) spectroscopy to characterize species containing paramagnetic centers. Since
this method is limited in resolution by inhomogeneous broadening, the
Quantronics team at SPEC has developed an innovative principle of ESR spectroscopy
that achieves the sensitivity required to measure individual spins at cryogenic
temperatures. This technique thus provides several orders of magnitude
improvement in spectral resolution. It has now been demonstrated on Er³? ions
with a gyromagnetic ratio of g = 8.3.

The objective of this thesis is to
develop methods for EPR spectroscopy of paramagnetic centers
with an effective gyromagnetic ratio close to g = 2. This
will enable EPR spectroscopy of individual molecules
for the first time and make it possible to study a wide range of organic radicals,
enzymes, and molecules containing paramagnetic transition metals
(Cu²?, Mn²?, …).