Characteristics of the structure and dynamics of the NH4IO3 crystal in the ferroelectric phase transition region
Abstract
The infrared, Raman, and nuclear quadrupole resonance spectra of the I-127 nuclei of the HN4IO3 crystal are investigated in the temperature range 295-400 K, near the ferroelectric phase transition point (367 K). It is found that heating in the range 320-335 K results in pre-transition 'orientational' melting accompanied by a restructuring of the system of H-bonds, rotation of NH4(+) ions, and an increased symmetry of NH4(+) and IO3(-) ions.
- Publication:
-
Ukrainskii Fizicheskii Zhurnal
- Pub Date:
- August 1985
- Bibcode:
- 1985UkFiZ..30.1239B
- Keywords:
-
- Ammonium Compounds;
- Crystal Structure;
- Ferroelectricity;
- Infrared Spectroscopy;
- Iodates;
- Phase Transformations;
- Molecular Ions;
- Nuclear Quadrupole Resonance;
- Positive Ions;
- Vibrational Spectra;
- Solid-State Physics