No. 20011 Deposited with http://cryst.instr.yamaguchi-u.ac.jp/20011
Journal: Journal of the Physical Society of Japan Vol.70 No.2 pp.569-575
Title: Crystal Structure and Phase Transition at Low Temperature in Betaine Phosphate
Authors: Takashi YOSHIDA, Hiroyuki MASHIYAMA+ and Tomoyuki MOCHIDA++
+ Department of Physics, Faculty of Science, Yamaguchi University, Yamaguchi 753-8512
++ Department of Chemistry, Faculty of Science, Toho University, Funahashi 274-0072
(Received July 28, 2000)
Abstract:
The low twmperature phase of betaine phosphate was investigated by X-ray diffraction.
It was found that the weak superlattice reflections appeared in the intermediate range (76K - 85K) between the paraelectric phase and the antiferroelectric phase.
Below 76K, the superlattice reflections intensified appreciably in the antiferroelectric phase.
The intensity of the X-ray diffraction at 20K was measured and analyzed to determine the crystal structure.
The least-squares method converged at the R factor 4.6% with 3349 reflections (4.2% for 2081 normal reflections and 8.4% for 1268 superlattice reflections).
The structure analysis clarified that the protons (the hydrogen atoms of the phosphate origin) between neighbouring phosphate tetrahedrons were in order in the low temperature phase causing the super structure of cell-doubling.
Keywords: Crystal structure, X-ray Diffraction, Betaine Phosphate
DEPOSITED DATA
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