Figure 2.

Result of the global fit of 13 SDF values J(ν_i) to the ²³Na relaxation data from the same sample as in Fig. 1 plotted as fast and slow longitudinal (R_1f and R_1s, ●) and transverse (R_2f and R_2s, ▴) relaxation rates. The estimated error bars are of the same size as the data symbols. For comparison, relaxation rates from single-frequency fits are also shown (without error bars) as open symbols: R₁^eff (○), R₂^eff (⋄, at lower fields), and R_2f and R_2s (▵, at higher fields). The curves are based on an assumed form of the SDF.