Rule 1: The starting point is p=0 for any nucleus (equivalent to I_z).

Rule 2: The final point for the detected nucleus is p=-1 (quadrature detection, equivalent to p=-1 that means I^-=I_x-iI_y) and p=0 for the other non-detected nucleus. Sometimes, it is advisable to use retrosynthetic analysis from the end of pulse sequence.

Rule 3: Only pulses can change the coherence order. Thus, during any evolution period the coherence is keep to the same value and only the intensity signal is modulated according to know relationships.

Rule 4: The pulses applied on a I nucleus only affect the coherence order of such nucleus, while the coherence orders of other nucleus (S) are not affected.

Rule 5: The starting point of any pulse sequence is a 90 pulse. In principle, this pulse creates equal amounts of coehrence orders +1 and -1 according to

I_z ------> -I_y = (i/2) (I⁺+I^-)

Rule 6: A 180 pulse only changes the sign of the available coherence orders from p to -p.

Rule 7: A 90 pulse applied to transverse operators can create any coherence order and therefore gradients or phase cycle will determine which will be selected.

Rule 8: When gradients are applying during a period, only a single pathway is selected according to the refocusing condition:

Rule 9: In multidimensional experiments, gradients applied during the variable evolution period only selects an specific order and therefore magnitude-mode data is obtained. Phase-sensitive data is only achived avoiding the application of a gradient during this period or applying the echo-antiecho approach.