Redox reactions of Co(edta) - with Ru(NH 3) 5L 2+ (L = 3- and 4-aminopyridine (AmPy)) were found to follow an outer-sphere electron transfer mechanism. The specific rate constants are (3.26 ± 0.03) × 10 2 and (3.07 ± 0.04) × 10 3 M -1S -1, for L = 3- and 4-AmPy, respectively, at μ = 0.10 M LiClO 4, pH = 8.0 (tris) and T = 25°C. The rate constants of oxidations for a series of Ru(NH 3) 5L 2+ complexes are higher than those of the corresponding Fe(CN) 5L 3- complexes by factors of 4 to 15 even after corrections for differences in reduction potentials and in charges of the complexes. Nonadiabaticity in the reactions of Fe(CN) 5L 3- complexes may account for the difference in the relative reactivities.
Relation:
Journal of the Chinese Chemical Society Volume 43, Issue 1, 1996, Pages 37-40
