For the double-quantum experiment whose pulse sequence is shown in Fig. 8.1 8 on page 204, it turns out that shifting the phase of all the pulses which precede t\ by 0 results in the t\ modulation being modified from cos ([Ω] +Ω2|t1|) to cos(|Ω1 + Ω2|t1 + 2ϕ).
Describe how you would implement the TPPI method in this sequence so as to generate a frequency discriminated spectrum.