N.M.R. spectra of theXnAA′Xntype

Abstract
Two uses of 13C satellites in X spectra of XnAA′Xn spin systems are discussed: (a) the derivation, from their fine structure, of coupling constant information unobtainable from the spectrum of the parent compound, and (b) their employment in heteronuclear double resonance experiments. The magnitudes of coupling constants to 13C and the relative signs of these and other coupling constants are obtained for tetramethyldiphosphine.