Energy of the 5d state relative to the conduction band in compounds

Electronic structure of defects in Sr2MgSi2O7:Eu2+,La3+ persistent luminescence material

“…This was based on the energy position of the Eu 2+ 8 S 7/2 ground level and is in agreement with the predictions made using the Dorenbos model [35][36][37][38]. An isolated oxygen vacancy state given by the DFT calculations is located at 1 eV above the valence band (VB) indicating the presence of a deep electron trap (Fig.…”

Spectral characteristics of germanium compounds having apatite structure

“…It can be seen that all the samples are characterized by the formation of transparent particles of irregular round shape and According to the scheme of energy levels proposed by Dorenbos [37,38], E fa is defined as the energy of the fundamental absorption edge and ΔE ex is the energy of interwell excitons 4f-5d equal to 0.35 eV. Using energy dispersive analysis, we calculated the content of Ca, Eu and O in Ca 2 La 8(1 À x) Eu 8x Ge 6 O 26 À δ compounds and from the content of defects in these matrices we evaluated the content of the activator ion (Fig.…”

Structure and luminescence properties of SrAl2O4:Eu2+, Dy3+ by Ba2+ and Ca2+ co-doping

“…What is more, the positions of two emission peaks in the phosphorescence do not change with a low amount of the Ca 2+ ions and Ba 2+ ions doping. When x is reduced to 0.6, SAM3 exhibits a broad blue-green emission band with peak at 507 nm, it can be attributed to 4f 6 5d 1 ↔ 4f 7 ( 8 S) transition position of Eu 2+ being strongly dependent on the crystal field strength of the host lattice and splitting of 4f 6 5d 1 being dependent on symmetry of the host lattice [18,19]. By the analysis of two-peaks fitting, the emission spectra of the SAM4, SAM5 and SAM6 are shown in Table 1.…”