  NMR pulse sequences that are modifications of the HSQC experiment are
proposed to observe ${}^{13}\textrm{C}$-coupled relaxation in AX, AX$_2$, and
AX$_3$ spin systems. ${}^{13}\textrm{CH}$ and ${}^{13}{\textrm{CH}}_2$ moieties
are discussed as exemplary AX and AX$_2$ spin systems. The pulse sequences may
be used to produce 1D or 2D proton NMR spectra.
