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Updated: Jul 6, 2026

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Nonequilibrium thermodynamics formalism for Marcus theory of heterogeneous and self-exchange electron-transfer rate
Richa Sethi1, M V Sangaranarayanan
1Department of Chemistry, Indian Institute of Technology, Madras, Chennai-600036, India.
Abstract:
The cross-exchange electron-transfer rate constant expression of Marcus is derived from the Flux-force formalism of non-equilibrium thermodynamics. The relationship governing the Onsager's phenomenological coefficients for cross-exchange and self-exchange electron-transfer processes is deduced. Onsager's phenomenological coefficient pertaining to the Butler-Volmer equation is derived and estimated from the experimental exchange current densities. The correlation between the heterogeneous and the homogeneous electron-transfer rate constants derived by Marcus is analyzed in terms of the corresponding phenomenological coefficients.
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