A zig-zag domain-wall structure of the incommensurate phase in A 2BX4-type crystals
نویسندگان
چکیده
2014 Within Landau theory of phase transitions in A2BX4 2014 type crystals we introduce in the free energy a new third-order Umklapp term. In the incommensurate phase this term can induce a new phase transition connected with a rotation of the wave vector of modulation away from the a* direction. The electrostatic energy in these improper ferroelectrics could induce in fact a zig-zag domain-wall structure, i.e. a structure also modulated along b*. J. Physique 47 (1986) 1785-1789 OCTOBRE 1986, Classification Physics Abstracts 64.70D 77.80D
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