Revised crystal structure and luminescent properties of gadolinium oxyfluoride Gd₄O₃F₆doped with Eu³⁺ions

Abstract

The structure of gadolinium oxyfluoride nanoparticles was revised. Extensive studies including X-ray diffraction and Rietveld refinement as well as Fourier transform infrared spectroscopy and Raman spectroscopy confirmed the monoclinic P12/c1 crystal structure of Gd4O3F6. Morphological analysis using transmission electron microscopy showed the nanocrystallinity of the materials prepared via the sol-gel Pechini's method. The luminescent properties of the prepared materials with different concentrations of Eu(3+) ions were characterized by emission spectroscopy. The phosphors obtained were investigated in the vacuum ultraviolet range using synchrotron radiation. The Judd-Ofelt parameters (Ω2, Ω4) and emission efficiencies η were calculated and are discussed in detail.

Synthesis, growth and photoluminescence behaviour of Gd2O2SO4:Eu3+nanophosphors: the effect of temperature on the structural, morphological and optical properties

“…In agreement with the FE-SEM results, the average breadth in the middle part of needles was measured in the range of 50-55 nm. 7 The obtained Raman results have good relationship with the discussed FTIR results. The Figure 5a represents FESEM-EDAX images of hydrated Gd 2 (SO 4 ) 3 at 400 °C, reveals that the particles were close to elongated spheroids with aggregation due to the temperature.…”

Press to Success: Gd5FW3O16—The First Gadolinium(III) Fluoride Oxidotungstate(VI)

“…These findings are also corroborated by both MAPLE [29][30][31] and bond valence calculations [34,35]. The effective coordination numbers (ECoN, [33]) of Gd1-4 are at best about 0.8 less than the real ones (Table 5), whereas (Gd5) 3+ exhibits an ECoN value of 6.3, which is only 70% of the nine surrounding oxide anions detected from the crystal structure description, due to this anisotropic distance distribution. The contribution of every single oxygen ligand to the effective coordination number displays a gap from the ideal value of 1 ± 0.2 for the four shortest ones to 0.63 for (O5) 2− and between 0.4 and 0.08 for the longest contacts.…”

“…These findings are also corroborated by both MAPLE [29][30][31] and bond valence calculations [34,35]. The effective coordination numbers (ECoN, [33]) of Gd1-4 are at best about 0.8 less than the real ones (Table 5), whereas (Gd5) 3+ exhibits an ECoN value of 6.3, which is only 70% of the nine surrounding The crystal structure of Gd 5 FW 3 O 16 further comprises three crystallographically distinguishable W 6+ cations, which are surrounded by six oxide anions each in shape of distorted octahedra (Figure 4). These coordination polyhedra are interconnected via edge-and vertex-sharing to discrete [(W1) 2 O 10 ] 8− and [(W2)(W3)O 11 ] 10− entities, respectively (Figure 4).…”

Controllable synthesis and selective doping of hexagonal GdF3 and spinel-like Ga2O3 nano-crystals in silicate glass

“…the standard Tanabe ions [28,29]. Generally, the intensity parameters are calculated from the absorption spectra.…”