Abstract 

MultipleChannel RotorSynchronized Pulse Sequences: Application to Heteronuclear Recoupling and Decoupling in Magic Angle Spinning NMR,
41st Experimental NMR Conference, Asilomar, California, USA
(Apr. 2000),
poster.
Recently a new class of rotorsynchronized pulse sequences, denoted RN_{n}^{ν} has been reported [1]. The sequences consist of N elements, each of which rotates the spins by an angle π around the xaxis. The phases of the elements are alternated by ±πν/N. The sequence of N elements span n rotational periods. Earlier on the concept of C7 [2] was generalized to sequences denoted by CN_{n}^{ν} [3,4], consisting of N cycles, with phases incremented in steps of 2πν/N. The sequence of N cycles spans n rotational periods. These types of sequences might be used simultaneously using multiplechannel rf irradiation. We present symmetry theorems for this application, which allow the construction of rf sequences to recouple and/or decouple certain spin interactions in heteronuclear spin systems in the presence of magic angle rotation of the sample. We present solutions for decoupling homonuclear dipolar and CSA interactions on two rf channels while recoupling the heteronuclear dipolar couplings. The sequences are used to measure heteronuclear ^{15}N^{13}C distances and to obtain two dimensional correlation spectra. Possibilities for improving heteronuclear decoupling during homonuclear recoupling are also discussed.


Dr. Andreas Brinkmann Measurement Science and Standards National Research Council 1200 Montreal Road, M40 Ottawa, Ontario K1A 0R6 Canada Tel. +16139900319 Fax. +16139901555 Andreas.Brinkmann@nrccnrc.gc.ca 

Dr. Andreas Brinkmann, NRCMSS, 1200 Montreal Road, M40,
Ottawa, ON K1A 0R6, Canada Andreas.Brinkmann@nrccnrc.gc.ca 