A 6-PULSE PASS MAS-NMR TECHNIQUE SOLVED BY A PHASOR METHOD

The PASS MAS-NMR technique is capable of recovering full intensities o f the central resonances of a spectrum by phase adjusting the spinning sidebands. This variant of the original PASS sequence by Dixon uses s ix pi pulses instead of four. The addition of two pi pulses provides m ore flexibility in choosing the spacing between pulses and therefore e liminates pulse overlap and receiver dead-time problems. The nonlinear , underdetermined PASS equations were solved using a graphical phasor method. All PASS sequences were successfully tested. A table of the si x pulse delay times for different pitches is presented. (C) 1998 Acade mic Press.