Proton tunneling neutron scattering

Figure 9. BA was the first system in which the tunneling contribution to the reaction rate at low temperatures was determined [52,147,148] and is the only system for which the tunneling matrix element for intermolecular PT has been measured [53,149,150]. The following sections summarize the optical studies on the material that led to these results and discuss recent work, using NMR and neutron scattering, aimed at a more complete characterization of the proton dynamics.

Figure 8.9 INS spectrum of KHCOj at 4 K in the tunnelling region and band decomposition into Gaussian profiles. Reproduced with permission from Chem. Phys. 124, F. Fillaux, J. Tomkinson and J. Penfold, Chem. Phys., Proton Dynamics in the Hydrogen Bond. The Inelastic Neutron Scattering Spectrum of Potassium Hydrogen Carbonate at 5K, 425, Copyright (1988) Elsevier.

Pelah, L, E. Wiener, and J. Imry, 1965. Indication of proton tunneling in KH2PO4 by comparing neutron inelastic scattering and infrared measurements. Inelastic Scattering Neutrons, Proc. Symp. 4th (Bombay 1964) 2 325. 

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