The two-dimensional angular correlation spectra of 2γ annihilation radiation (2D-ACAR) from single crystals of (Formula presented) at 30, 150, and 290 K and (Formula presented) at 150 and 290 K have been measured. A structural deformation in (Formula presented) has been observed through the change of the momentum distribution of the positronium. The similarity of the anisotropies of the 2D-ACAR spectra for (Formula presented) and (Formula presented) in the rhombohedral structure indicates that a similar structural deformation also takes place in (Formula presented) This deformation can be the trigger of the spin-crossover transition.
|Number of pages||4|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 1998 Jan 1|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics