Tunneling of coupled methyl groups in lithium acetate: The isotope effect
Tóm tắt
We studied by high resolution inelastic neutron scattering the isotope effect of tunneling of coupled methyl groups in lithium acetate dihydrate (LIAC). Fully protonated, fully deuterated and mixed LIAC samples were investigated. The results are described by a simple model in which it is assumed that the single particle potential hindering rotation is strongly increased by deuteration, whereas the coupling potential is nearly unchanged. This allows to interpret the very strong isotope effect and also the spectra of the mixed compounds. The strong increase of the single particle potential by deuteration is tentatively explained by phonon mediated coupling.
Tài liệu tham khảo
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