Journal of Physical Chemistry, Vol.99, No.14, 4970-4975, 1995
Solvent Effects on Reactivity of Solvated Electrons with Nitrate Ion and on Electrolyte Conductivity in C-1 to C-10 N-Alcohols
The reaction rate constants k(2) for solvated electron reaction with nitrate ions in C-1 to C-10 n-alcohols increase with increasing viscosity eta and longitudinal relaxation time tau(L) of the solvent. This relatively slow reaction is assisted by a longer encounter duration, hence a larger tau(L) and eta. The smallest value of the mean time required for an encounter pair to react, k(r)(-1), occurs in the alcohol with the largest tau(L) and eta, and the other way around. In methanol, k(r)(-1) much greater than tau(L), whereas in 1-octanol and 1-decanol, k(r)(-1) < tau(L). At the extremes, in methanol and decanol, the activation energy E(2) of the overall reaction is similar to that of ion mobility or of the fluidity of the solvent, whereas in intermediate alcohols E(2) is much larger than those of mobility or fluidity. The reaction of e(s)(-) with nitrate is activation entropy limited in methanol, mainly activation energy limited in C-2 to C-4 n-alcohols, and mainly diffusion/dipole rotation limited in 1-decanol.