Abstract

AbstractUsing Landau theory of phase transitions it is shown that in the langbeinite structure (space group T4) four spatially homogeneous structural phase transitions are possible. Theree of them are improper ferroelectric and result from a phonon instability at the M point of the Brillouin zone. The fourth one is very similar to structural phase transitions in hig temperature superconductors of the β‐tungsten structure. The free energies providing a basis for macroscopic description of these phase transitions are presented.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call