This is the original model for 2-site fast exchange for CPMG-type experiments. It is selected by setting the model to `LM63', here named after Luz and Meiboom (1963). The original n-site Equation (7) from their paper can be written as
Rex = 1 - 2τexg⋅tanh2τexg⋅τex⋅piΔωi, | (11.14) |
where g is the pulse repetition rate defined as
g = 2νCPMG. | (11.15) |
It can be rearranged as
The equation for the 2-site exchange process can be expressed as
R2eff = R20 + ⋅1 - ⋅tanh. | (11.17) |
The reference for this equation is:
More information about the LM63 model is available from:
The relax user manual (PDF), created 2020-08-26.