For the molecule shown opposite, a transient NOE experiment (recorded in the initial rate limit) in which HB was inverted gave equal NOE enhancements (in the initial rate limit) on HA and HC. If HA was inverted, the enhancement on HB was the same as in the first experiment; no enhancement was seen on HC.
In steady-state experiments, irradiation of HB gave equal enhancements on HA and HC. However, irradiation of HA gave a much smaller enhancement on HB than for the case where HB was the irradiated spin and the enhancement was observed on HA. Explain these observations.