1997/06/19 by Stephen J. Paddison, Lawrence R. Pratt, Paddison, Stephen J. +5
Engineering · Physics and Astronomy · #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Fuel Cells and Related Materials #Molecular Junctions and Nanostructures #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.physics/9706028
openalex publication_date 1997/06/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Reported here are theoretical calculations on the triflic acid and water, establishing molecular scale information necessary to modeling of the structure, thermodynamics, and ionic transport of Nafion membranes. To characterize side chain flexibility and accessibility of the acid proton, free energies for rotation of both carbon-sulfur and sulfur-oxygen (hydroxyl) bonds are presented. The energetic barrier to rotation of the acid proton away from the sulfonic acid oxygen plane is substantially flattened, with barrier less than one kcal/mol, by electrostatic solvation. The activation free energy for acid-water proton interchange is about 4.7 kcal/mol.