Deuteron momentum distribution in KD2PO4

  title={Deuteron momentum distribution in KD2PO4},
  author={George F. Reiter and A. Shukla and Philip M. Platzman and Jerry Mayers},
  journal={New Journal of Physics},
The momentum distribution in KD2PO4 (DKDP) has been measured using neutron Compton scattering above and below the weakly first-order paraelectric–ferroelectric phase transition (T=229 K). There is very little difference between the two distributions, and no sign of the coherence over two locations for the proton observed in the paraelectric phase, as in KH2PO4 (KDP). We conclude that the tunnel splitting must be much less than 20 meV. The width of the distribution indicates that the effective… 

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