Figure 5.

R_1ρ relaxation dispersion curves for 2-site chemical exchange. (black, solid) Numerical eigenvalue, (orange, dashed), Trott-Palmer expression, Eq. 30, (blue, dotted), Eq. 32. Parameters common to all calculations are ω₂₁/(2π) = 200 Hz, p₂ = 0.05, and R₁₁ = R₁₂ = 2.5 s⁻¹. Other parameters are (a) k_ex = 250 s⁻¹, ω₁/(2π) = 25 Hz, R₂₁ = R₂₂ = 6 s⁻¹; (b) as in (a) except k_ex = 1200; (c) ω_rf/(2π) = 0 Hz, k_ex = 400 s⁻¹, R₂₁ = R₂₂ = 6 s⁻¹; (d) as in (c) except R₂₂ = 60 s⁻¹; (e) ω_rf/(2π) = 0 Hz, ω₁/(2π) = 100 Hz, R₂₁ = R₂₂ = 6 s⁻¹; and (f) as in (e), except R₂₂ = 60 s⁻¹.