MODE-SPECIFIC QUANTUM RATE EFFECTS FOR INTERFACIAL ELECTRON-TRANSFER - COMPUTATIONAL CASE-STUDIES BASED UPON 4-CYANO-N-METHYLPYRIDINIUM REDUCTION

Citation
Dc. Selmarten et Jt. Hupp, MODE-SPECIFIC QUANTUM RATE EFFECTS FOR INTERFACIAL ELECTRON-TRANSFER - COMPUTATIONAL CASE-STUDIES BASED UPON 4-CYANO-N-METHYLPYRIDINIUM REDUCTION, Journal of the Chemical Society. Faraday transactions, 92(20), 1996, pp. 3909-3916
Citations number
38
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
ISSN journal
09565000
Volume
92
Issue
20
Year of publication
1996
Pages
3909 - 3916
Database
ISI
SICI code
0956-5000(1996)92:20<3909:MQREFI>2.0.ZU;2-H
Abstract
Multi-mode quantum rate theory is used to examine the interfacial kine tics of a prototypical organic-radical-generating reaction: the reduct ion of the 4-cyano-N-methylpyridinium cation. Charge-transfer-enhanced Raman scattering experiments (R. L. Blackbourn, et al., J. Phys. Chem ., 1991, 95, 10535) previously showed that 13 vibrational modes are co upled to the reduction process. From a time-dependent analysis of the scattering spectrum, precise coordinate displacement and reorganizatio nal parameters for each of the modes have now been determined. These p arameters, when incorporated into the rate theory, have yielded an ext remely detailed-perhaps unprecedented-description of electrochemical r eaction kinetics, including complete descriptions of: (a) mode-specifi c barrier effects, (b) mode-specific tunnelling effects, (c) non-class ical activation effects and (d) sum-over states driving force effects.