Structural and crystal chemical properties of rare-earth titanate pyrochlores

Emergent order in the kagome Ising magnet Dy3Mg2Sb3O14

“…2c). This puzzle is elucidated by Monte Carlo simulations for a minimal model containing the nearest-neighbour exchange interaction J =−3.72 K determined for structurally-related Dy 2 Ti 2 O 7 (refs 22, 27), and the long-range magnetic dipolar interaction D =1.28 K calculated from experimentally determined Dy–Dy distances. In 2D, spin canting interpolates between two limits—an ECO transition followed by lower-temperature spin ordering for in-plane spins8, and a single spin-ordering transition for spins perpendicular to kagome planes28—and hence destabilizes ECO compared with the 2D in-plane limit.…”

“…The local Dy environment in Dy 3 Mg 2 Sb 3 O 14 is similar to the cubic spin ice Dy 2 Ti 2 O 7 (ref. 22) (Supplementary Fig. 3), suggesting that Dy 3+ spins have an Ising anisotropy axis directed into or out of the kagome triangles with an additional component perpendicular to the kagome planes.…”

Nd and Ce simultaneous substitution driven structure modifications in Gd2−xNdxZr2−yCeyO7

“…The Lu 2 (Ti 2−x Lu x )O 7−x/2 compounds were prepared by Li et al 19 The results indicate that stuffing more Lu 3+ cations into the oxide structure leads eventually to an order-to-disorder transition, from an ordered pyrochlore to a disordered fluorite crystal structure. In addition, Farmer et al 20 found that the cubic lattice parameters of RE 2 Ti 2 O 7 (where RE = a rare-earth) displayed an approximately linear correlation with the RE site cation radius. Although considerable works have been focused on investigating the phase and structure evolutions by the A site substitution or B site substitution of pyrochlore A 2 B 2 O 7 structure, information concerning the structure evolutions resulted by both A and B sites simultaneous substitution is still incomplete owing to no work devoted to this topic.…”

The effect of synthesis conditions on the structure of compounds formed in the Dy2O3–TiO2 system

“…More information about the structure of compounds synthesized by annealing of X-ray amorphous precursors was derived from Raman spectra, which allows to follow the anion ordering in the crystal phases formed (in particular, the pyrochlore phase Dy 2 Ti 2 O 7 [22]). …”