We next explored the occurrence of exchange-induced cross-peaks in heteronuclear singleand multiple-quantum coherence experiments (HSQC and HMQC respectively). Heteronuclear experiments are typically more complex pulse sequences, containing extended coherence transfer periods and zz filters, which create multiple possibilities for chemical exchange to affect the spectra. Chemical exchange broadening is well understood to reduce the efficiency of coherence transfer in DEPT and INEPT experiments near intermediate exchange regimes, but the possibility of coherent exchange of transverse magnetisation between states (outside of the fast exchange regime) does not appear to have been recognised.