USE OF RF GRADIENTS IN EXCITATION SCULPTING, WITH APPLICATION TO 2D HSQC

The gradient pulses of double-GBIRD can be replaced with high-power sp in-lock pulses (RF gradients) in z-rotation composite sandwiches, Impl ementation of this double-spin-locked BIRD (double-SLBIRD) in 2D HSQC results in drastic suppression of t(1) noise, nice baseline characteri stics, and good dynamic range. The superior properties of double-SLBIR D-HSQC over conventional HSQC and even over double-spin-locked HSQC fo r small to medium-sized molecules makes this excitation-sculpting appr oach preferable, However, double-SLBIRD should not be considered as an alternative for double-GBIRD, but rather as a substitute for those sp ectrometers lacking field gradients. (C) 1997 Academic Press.