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h i g h l i g h t s LaSbO 4 compounds were produced by solid-state method. Structural characterization was conducted by XRD and Raman scattering. Polarized Raman spectroscopy in sintered ceramics allowed us a complete modes assignment. Luminescence properties revealed a promising phosphor.

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X-ray diffraction and Raman spectroscopy were employed to analyze the effect of the rare earth (RE) doping (ionic radii and concentration) on the crystalline structure of Sr0.97RE0.03TiO3 (RE = Sm3+, Eu3+, Gd3+, Dy3+, Tm3+, Yb3+, Lu3+) and Sr1–x Eu x TiO3 (x varying from 0.01 to 0.19) ceramic powders. We notice drastic changes in both structural and vibrational properties of the investigated samples for increasing dopant concentration into the SrTiO3 (ST) lattice. The results showed evidence of RE incorporation into both A- and B-sites of the ST structure. Also, tetragonal local symmetry (I4/mcm space group) was observed in RE-doped samples at room temperature from the cubic (Pm3̅m) phase exhibited by phase-pure ST ceramics. The results obtained for the Sr1–x Eu x TiO3 ceramic powders showed that these samples undergo a clear cubic-to-tetragonal phase transition for x ≥ 0.13 at room temperature.

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PrLuO interlanthanides were prepared at temperatures ranging from 800 °C to 1600 °C using hydrothermally-derived precursors. The chemical reactions observed include the conversion and segregation of Pr(OH) and LuO(OH), respectively, into PrO and LuO cubic oxides below 1200 °C, followed by the production of a mixture of hexagonal P6/mmc and orthorhombic Pnma PrLuO phases at 1400 °C. Phase-pure orthorhombic PrLuO was obtained at 1600 °C, which was corroborated by Raman and micro far-infrared spectroscopic analyses. Photoluminescence, colorimetric and lifetime measurements were carried out in PrLuO samples. Dominant emission verified in samples calcined at 1400 °C corresponds to the hypersensitive P → F transition with a color purity of 97% (decay times of 12 μs and 3 μs), while emissions for the phase-pure samples correspond to the P → H and P → H transitions with a color purity of 94% (a single luminescence lifetime of 12 μs). The optical properties of PrLuO interlanthanides thereby suggest that they can be used as luminescent materials in both structural arrangements.

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Phase‐pure monoclinic NdLuO3 is prepared by hydrothermal reaction of an alkaline (pH <13) solution of Nd(NO3)3 and Lu(NO3)3 (autoclave, 250 °C, 24 h) resulting in the nanocrystalline precursors LuO(OH) and Nd(OH)3 which are further calcined, compressed, and sintered in air (1600 °C, 8 h).