IT99

This is the relaxation dispersion model for 2-site exchange on all times scales (with the constraint that p_A >> p_B named after Ishima and Torchia (1999). The reference is:

• Ishima, R. and Torchia, D. (1999). Estimating the time scale of chemical exchange of proteins from measurements of transverse relaxation rates in solution. J. Biomol. NMR, 14(4), 369-372. (doi: 10.1023/A:1008324025406).