title: Entropy and enthalpy contributions to the kinetics of proton coupled electron transfer to the Mn4O4(O2PPh2)6 cubane.
abstract: The dependence of rate, entropy of activation, and ((1)H/(2)H) kinetic isotope effect for H-atom transfer from a series of p-substituted phenols to cubane Mn4O4L6 (L = O2PPh2) (1) reveals the activation energy to form the transition state is proportional to the phenolic O-H bond dissociation energy. New implications for water oxidation and charge recombination in photosystem II are described.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, NJ 08540, USA.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Carrell
authors.forename: Paul F
authors.initials: PF
authors.lastname: Smith
authors.forename: Joseph
authors.initials: J
authors.lastname: Dennes
authors.forename: G Charles
authors.initials: GC
authors.lastname: Dismukes
mesh_terms: D004579:Electron Transport; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D011522:Protons; D013816:Thermodynamics
chemical_list: D017895:Manganese Compounds; D011522:Protons