Electron paramagnetic resonance measurements have been performed in si
ngle crystals of copper(II) saccharinate, [Cu(C7H4NO3S)(2)(H2O)(4)]. 2
H(2)O, as a function of the magnetic field orientation. The characteri
stics of the spectra are dominated by the exchange narrowing phenomeno
n which partially collapses the hyperfine structure, and the resonance
s due to magnetically different copper ions in the unit cell. The data
are used to estimate the magnitude of the exchange couplings between
copper ions in the compound and the results are discussed in terms of
the structural data.