Figure 4.

Experimental $T_2^{\text{'}}$ as a function of 1/${\nu }_0^{\mathrm{H}}$ under optimised TPPM, SPINAL‐64 and XiX decoupling, corresponding to the points marked in Figure 3, as well as under CW. Datasets acquired using ${\nu }_{\mathrm{r}}=12\mathrm{kHz}$ and ${\nu }_1=105\mathrm{kHz}$ (XiX used ${\nu }_{\mathrm{r}}=11.905\mathrm{kHz}$ to ensure synchronisation of pulse width increments with the MAS period). Hardware configurations 1–4 were used, with CP contact times of 2.7, 1.2, 2.7 and 1.8 ms respectively (see Table 1). Uncertainties in the fitted values of $T_2^{\text{'}}$ were of the order of the marker sizes or smaller.