Broadband heteronuclear Hartmann-Hahn sequences with short cycle times.

For some applications, broadband heteronuclear Hartmann-Hahn sequences with very short cycle times are required. A quality factor is presented that makes it possible to assess the relative sizes of cycle time, bandwidth, and maximum RF amplitude for any given multiple-pulse sequence. This quality factor is determined for multiple-pulse sequences that are commonly used in HEHAHA experiments and for some favorable sequences that were so far only discussed in the context of heteronuclear decoupling.