Improvement of INADEQUATE using compensated delays and pulses

A J-compensated homonuclear spin-echo sequence is developed from the 90_α^o180_α+2π/3^o composite pulse using a product-operator analogy between homonuclear spin-spin coupling and RF pulses, and a J-compensated INADEQUATE sequence is constructed using this spin-echo sequence. Detailed study of the efficiencies of various composite pulses in minimizing resonance-offset effects in INADEQUATE experiments showed that five-step symmetric phase-altemating composite pulses are most effective. The sequences C-INADEQUATE, which incorporates composite pulses, and JC-INADEQUATE, which includes both offset and J-compensation, are shown to have a sensitivity significantly higher than that of conventional INADEQUATE.