On the structural evidence for a direct proton tunnelling effect in the KH2PO4-type transition
- 30 August 1988
- journal article
- Published by IOP Publishing in Journal of Physics C: Solid State Physics
- Vol. 21 (24) , L881-L886
- https://doi.org/10.1088/0022-3719/21/24/001
Abstract
High-resolution neutron diffraction results for KH2PO4 (KDP) and its deuterated form (DKDP) have been used to re-examine evidence that the large increase in the phase transition temperature, Tc, on deuteration can be explained simply by the increase in the phase transition temperature, Tc, on deuteration can be explained simply by the increase in the O...O hydrogen-bond length, 2R, without invoking proton tunnelling effects. It is shown that deuteration at constant 2R still gives rise to an increase in Tc by about 40 K. This may represent the direct proton tunnelling effect on Tc. However, there are other geometric changes on deuteration at constant 2R, and the effect of these needs to be assessed before any more definite conclusion can be reached.Keywords
This publication has 18 references indexed in Scilit:
- Negative evidence for a proton-tunneling mechanism in the phase transition of-type crystalsPhysical Review B, 1987
- Structural studies of KDP and the KDP-type transition by neutron and x-ray diffraction: 1970–1985Ferroelectrics, 1987
- On the pressure dependence of the crystal structure of squaric acid (H2C4O4)Journal of Physics C: Solid State Physics, 1986
- Further Comment on Isotope Effect in Hydrogen Bonded CrystalsProgress of Theoretical Physics, 1984
- Note on Isotope Effect in Hydrogen Bonded CrystalsProgress of Theoretical Physics, 1982
- Correlation between two isotope effects in hydrogen-bonded crystals: transition temperature and separation of two equilibrium sitesChemical Physics Letters, 1981
- Estimating the proton potential in kdp from infrared and crystallographic dataFerroelectrics, 1981
- The temperature and pressure dependence of the proton tunnelling frequency in KDPJournal of Physics C: Solid State Physics, 1980
- The O–H vs O.O distance correlation, the geometric isotope effect in OHO bonds, and its application to symmetric bondsActa Crystallographica Section B: Structural Science, Crystal Engineering and Materials, 1978
- On the isotopic effects in the ferroelectric behaviour of crystals with short hydrogen bondsJournal of Physics and Chemistry of Solids, 1960