The model-free models

Extending the list of models given in Orekhov et al. (1999a); Korzhnev et al. (2001); Fushman et al. (1997); Mandel et al. (1995); Zhuravleva et al. (2004), the models built into relax include

m0 &= \{\},\\
m1 &= \{S^2\},\\
m2 &= \{S^2, ...
...au_f, S^2_f, \tau_s, R_{ex}\},\\
m9 &= \{R_{ex}\}.\end{align}\end{subequations}
The parameter Rex is scaled quadratically with field strength in these models as it is assumed to be fast. In the set theory notation, the model-free model for the spin system i is represented by the symbol $\mathfrak{F}_i$. Through the addition of the local τm to each of these models, only the component of Brownian rotational diffusion experienced by the spin system is probed. These models, represented in set notation by the symbol $\mathfrak{T}_i$, are
tm0 &= \{\tau_m\},\\
tm1 &= \{\tau_m, S^2\},\...
..._f, \tau_s, R_{ex}\},\\
tm9 &= \{\tau_m, R_{ex}\}.\end{align}\end{subequations}

The relax user manual (PDF), created 2020-08-26.