Broadband homonuclear recoupling

Hou et al. have recently described a family of experiments for R2 Driven Spin Diffusion (RDSD) spectroscopy suitable for homonuclear correlation experiments under fast MAS conditions. In these RDSD experiments, since the broadened second-order rotational resonance conditions are dominated by the rf field strength and the phase shifts, as well as the size of reintroduced dipolar couplings, the different R2 sequences display unique polarization transfer behaviours and different recoupling frequency bandwidths. In the subsequent report, Hou et al. present a series of modified R2/ sequences, dubbed combined R2 -Driven (CORD), that yield broadband homonuclear dipolar recoupling and give rise to uniform distribution of cross peak intensities... 

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