ABSTRACT
This chapter focuses on systems contacting more electron spins
(i.e. more paramagnetic centers). Strong dipole-dipole interactions
between the electron spins considerably influence the shape of
electron spin resonance (ESR) spectra and electronic relaxation.
The observed effects are dependent on the time scale of stochastic
fluctuations of the spin couplings. Discussing different kinds of spin
interactions, the influence of the 14N nitrogen quadrupole coupling
on the electron and proton spin relaxation in solutions of nitrogen
radicals is examined.
