Structural phase transition induced by the Jahn-Teller effect. Antiferrodistortive ordering

1976 ◽  
Vol 25 (4) ◽  
pp. 369-380 ◽  
Author(s):  
G. Schr�der ◽  
H. Thomas
1992 ◽  
Vol 291 ◽  
Author(s):  
Michael D. Kaplan

ABSTRACTA microscopic mechanism for the structural phase transition from the orthorhombic mediate temperature (OMT) phase into the low temperature tetragonal (LTT) one is suggested on the basis of the cooperative pseudo Jahn-Teller effect. The local distortions mixing the ground and the first excited electronic states are ordered antiferrodistortively and are connected in part, with the oxygen octahedra rotations around the [100] axis. The results are in agreement, with the neutron scattering experiments data.


1982 ◽  
Vol 73 (2) ◽  
pp. K243-K247 ◽  
Author(s):  
I. Onyszkiewicz ◽  
N. T. Malafaev ◽  
A. A. Murakhovskii ◽  
J. Pietrzak

1997 ◽  
Vol 53 (1) ◽  
pp. 102-112 ◽  
Author(s):  
P. F. Schofield ◽  
K. S. Knight ◽  
S. A. T. Redfern ◽  
G. Cressey

Rietveld analysis of neutron powder diffraction data on the sanmartinite (ZnWO4)-cuproscheelite (CuWO4) solid solution has enabled the comparison of microscopic and macroscopic order parameters associated with the P2/c–P\overline 1 structural phase transition. The macroscopic spontaneous strain, calculated from the lattice parameters, conforms well with a second-order Landau model. Furthermore, this is also true of the symmetry-related atomistic M—O order parameter and the quadratic elongation of the MO6 octahedra. It is clear that the Jahn–Teller effect, associated with the divalent Cu cation, is the driving force for the phase transition and the excess elongation evident in the M—O(2) bond giving rise to the non-symmetry predicted strain element e 22. The existence of a large region of order parameter saturation at the copper-rich end of the solid solution is also associated with the MO6 elongation and the breakdown of the homogeneous strain field of the zinc solute atoms.


2013 ◽  
Vol 46 (10) ◽  
pp. 104003 ◽  
Author(s):  
Peter A Ivanov ◽  
Diego Porras ◽  
Svetoslav S Ivanov ◽  
Ferdinand Schmidt-Kaler

Sign in / Sign up

Export Citation Format

Share Document