Phase transitions in the perovskitelike A2BX4 structure.

نویسندگان

  • Hatch
  • Stokes
  • Aleksandrov
  • Misyul
چکیده

A comparison is made of two different approaches to the description of phase transitions in the A2BX4 structure (space group D4&, I4/mmm) due to rigid octahedral tiltings. The lower-symmetry subgroups due to coupling of the K»f (X2) and E&2~ (P4) representations (6 tilts) to other tilting modes are listed. All observed transitions in the A2BX4 structure are of the octahedral tilting types. These are listed and correlated with the driving representations.

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عنوان ژورنال:
  • Physical review. B, Condensed matter

دوره 39 13  شماره 

صفحات  -

تاریخ انتشار 1989