Table 2.
Freq. (GHz) | S1(2.54) | S2(3.45) | X(9.2) | K(18.5) | Q(34.6) | W(94) |
---|---|---|---|---|---|---|
T1(µs) | 0.69 | 0.94 | 2.54 | 3.46 | 3.69 | 2.05 |
W(x)(µs−1) | 2.68 | 2.71 | 2.67 | 2.54 | 2.68 | 3.02 |
W(x) = T1−1(air,x) – T1−1 (N2,x), where T1 values are the spin-lattice relaxation times of the nitroxide in samples equilibrated with atmospheric air and nitrogen, respectively. W(x) is proportional to the product of the local translational diffusion coefficient and the local concentration of oxygen at a “depth” x in the lipid bilayer that is in equilibrium with atmospheric air.