Paper No S10.4: Transmission Electron Microscope Study of Symmetry‐related Transitions in Cubic Y₂O₃:Tb³⁺

Abstract

In this paper, we describe measurements of the cathodoluminescence of nanosized cubic Y 2 O 3 :Tb 31 with a transmission electron microscope. From the CL-spectra we determined the energy flow from excited Tb 31 in a S 6 lattice site to Tb 31 in a C 2 site.

Modification of the spectroscopic properties of Tb2O3 phosphor under the high-pressure phase transitions sequence

“…As previously stated, in the C-type structure of Tb 2 O 3 there are two different sites for Tb 3+ cations, which have C 2 and C 3i symmetry in a ratio 3:1, where the abundant site is the one with C 2 symmetry. In the isostructural Y 2 O 3 doped with 0.2% Tb 3+ , both sites have been clearly identified (Fig.6(a)), which is in agreement with what has been reported in the literature for that compound doped with different amount of Tb 3+ ions [31],[32]. However, this is not the case of the pure Tb 2 O 3 compound, where the RT emission spectrum (in green, Fig.6(a)) is identical to that assigned to C 2 site by fluorescence lifetimes.…”