H-1 NMR spectra with narrow, well-resolved resonances are reported for a set of binuclear copper(II) complexes, [Cu-2(L-R)(X)](ClO4)(2). A quantitative relationship exists between the chemical shift of selected peaks and magnetic coupling between the paramagnetic centers over a wide range (2J = +26 to -1100 cm(-1)) of coupling constants. Such spectra are shown to be useful in assaying sample purity and in estimating magnetic coupling constants.