COMPARATIVE-STUDIES OF PHASE-CYCLING SCHEMES FOR MULTIPLE PI-PULSE SEQUENCES

Recently, a new phase cycling scheme was introduced by this laboratory for use in biological solid-state NMR experiments involving multiple pi-pulses with characteristics that suggested it may enhance the sensi tivity of these kind of experiments (Y. Li and J. N. S. Evans, 1995, C hem, Phys. Lett. 241, 79 and Erratum, 1995, ibid. 246, 527; Y. Li and J. N. S. Evans, 1996, J. Magn. Reson. B 111, 296), The new sequence fo llowed the supercycled concept proposed a decade ago for heteronuclear decoupling experiments. In this paper, more detailed experiments demo nstrate that the claim of enhanced sensitivity was unfounded, and in f act the supercycle proposed differs little from the established XY-S a nd XY-16 based supercycles. (C) 1997 Academic Press.