Investigation on the Symmetry and the Order Parameter of the Displacive Antiferroelectric Phase Transition

Abstract

The shortage of the order parameter of the antiferroelectric phase in the previous reference is pointed out. An axial vector R = ∑ _iq_i r_i × Δ r_i/V was proposed as the order parameter of the displacive antiferroelectric phase. This vector is of the symmetry groupC _{∞ i} . Using R as the order parameter, we reinvestigated the antiferroelectric model of Kittle type. We find that the vector can adequately reflect the symmetry change of the paraelectric-antiferroelectric phase transition by using Curie principle.

Keywords:

• Displacive antiferroelectric phase transition
• order parameter
• symmetry
• Curie principle

PACS:

• 61.50.Ah
• 45.10.Na
• 02.20.Hj

Acknowledgment

This work was supported by the National Natural Science Foundation of China under Grant No. 10647120 and by the Research and Development Project of Hebei Provincial Science and Technology under Grant No. 06547002D-2.