ON THE EQUIVALENCE OF THE PSEUDOPHASE RELATED MODELS AND THE BRO ¨ NSTED APPROACH IN THE INTERPRETATION OF REACTIVITY UNDER RESTRICTED GEOMETRY CONDITIONS C. Go´ mez Herrera, R. Jime´nez, P. Pe´rez-Tejeda, P. Lo´ pez-Cornejo, R. Prado-Gotor and F. Sa´ nchez* Contribution from the Department of Physical Chemistry, Faculty of Chemistry, University of Seville C/ Profesor Garcı´a Gonza ´lez s/n. 41012 Sevilla, Spain Contents 1. INTRODUCTION 290 2. DISCUSSION: EQUIVALENCE OF THE PSEUDOPHASE MODEL AND THE BRO ¨ NSTED APPROACH 292 2.1 Unimolecular reactions 292 2.2 Bimolecular reactions 297 2.3 The two reactants can be in the two states (free and bound) 299 3. FINAL COMMENTS 308 4. ACKNOWLEDGMENT 309 5. REFERENCES AND NOTES 309 ABSTRACT The equivalence of the Pseudophase and related models, frequently used in the interpretation of kinetic data under restricted geometry conditions, and the well known Bro¨nsted’s equation, used in the interpretation of the reactivity in homogeneous media, has been proven in several cases. The generalisation in relation to other non-kinetic properties such as reaction free energy and redox potentials has also been considered. Prog React Kinet Mech 29: 289–310 # 2004 Science Reviews ———————— *To whom correspondence should be addressed: E-mail: gcjrv@us.es Progress in Reaction Kinetics and Mechanism. Vol. 29, pp289–310. 2004 1468-6783 # 2004 Science Reviews 289