The temperature dependences of extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectra of Ln2Ti2O7 (Ln = Gd, Tb, Dy) geometrically frustrated magnets with a pyrochlore structure are presented. The temperature dependences of the Ln-O and Ti-O interatomic bond lengths and Debye-Waller factors σ2 characterizing the local static and dynamic disordering of bonds have been obtained in the temperature range of 10–300 K. The stiffnesses of metal-oxygen bonds and the parameters of local disordering of the structure have been determined from the dependences σ2(T). The effect of the magnetic state of rare-earth ions on local features of the Ln2Ti2O7 structure has been described. The characteristics of local disorder in pyrochlores under study have been compared to dysprosium zirconate Dy2Zr2O7 having a disordered fluorite structure.
Menushenkov A.P., Popov V.V., Gaynanov B.R., Ivanov A.A., Kuznetsov A.V., Yaroslavtsev A.A., et al. (2019). Local Disorder in Ln2Ti2O7 (Ln = Gd, Tb, Dy) Pyrochlores. JETP LETTERS, 109(8), 529-535 [10.1134/S0021364019080095].
Local Disorder in Ln2Ti2O7 (Ln = Gd, Tb, Dy) Pyrochlores
Puri A.
2019
Abstract
The temperature dependences of extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectra of Ln2Ti2O7 (Ln = Gd, Tb, Dy) geometrically frustrated magnets with a pyrochlore structure are presented. The temperature dependences of the Ln-O and Ti-O interatomic bond lengths and Debye-Waller factors σ2 characterizing the local static and dynamic disordering of bonds have been obtained in the temperature range of 10–300 K. The stiffnesses of metal-oxygen bonds and the parameters of local disordering of the structure have been determined from the dependences σ2(T). The effect of the magnetic state of rare-earth ions on local features of the Ln2Ti2O7 structure has been described. The characteristics of local disorder in pyrochlores under study have been compared to dysprosium zirconate Dy2Zr2O7 having a disordered fluorite structure.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
