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Updated: Jul 12, 2026
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Elucidation of the Antiferroelectricity Mechanism in CsBi(MoO4)2
Andries van Hattem1, Gilles Wallez2, Nick T H Ter Veer1
1Radiation Science and Technology Department, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, Delft 2629JB, The Netherlands.
None:
Although the antiferroelectric compound CsBi-(MoO4)2 has been known for a long time, the underlying mechanism remained poorly understood. No temperature-dependent crystallographic investigation was performed to solve this. In this work, a neutron diffraction study at 150 K was used to solve the crystal structure of the antiferroelectric phase existing between 135 and 330 K. X-ray absorption spectroscopy at room temperature and temperature-dependent diffraction studies between 150 K and the melting point were used to elucidate the mechanism driving the phase transition. The antiferroelectricity mechanism of CsBi-(MoO4)2 is revealed to be driven by the temperature-dependent Bi displacement caused by the Bi 6s 2 lone pair. The thermal expansion of CsBi-(MoO4)2 between 150 K and its melting point is determined, as well. The current work solves the long-standing question of the origin of the antiferroelectricity in CsBi-(MoO4)2.
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