Abstract:
The temperature-dependent broadening of the electron paramagnetic resonance spectra observed
in aqueous solutions of the paramagnetic surfactants 2,2,6,6-tetramethylpiperidine-oxidedccyldimethylammonium
bromide, 2,2,6,6-tetramethylpiperidine-oxidedodecyldimethylammonium bromide
and 2,2,6,6-tetramethylpiperidine-oxidetetradccyldimethylammonium bromide is not caused by
monomer-micelle exchange in those solutions. It is probably due to the different effectiveness of
monomers and micelles in causing Heisenberg spin exchange, complicated by the temperature
variation of the c.m.c. and by possible dimerization of the nitroxide head group.
