Analysis of the shift of zero-phonon lines for f–d luminescence of lanthanides in relation to the Dorenbos model

Zych, Aleksander; Ogiegło, Joanna M.; Ronda, Cees; Donegá, Celso de Mello; Meijerink, Andries

doi:10.1016/j.jlumin.2012.08.052

Cited by 14 publications

(12 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this connection it is interesting to compare the results to those for YAG:Tb where the HS−LS splitting is calculated to be 5 285 cm −1 from the onset of the LS band at 280.7 nm and the ZPL for the HS band at 329.6 nm. 17 This indicates that the covalency for Ce 3+ in the YAG lattice is larger than for Ce 3+ in the LuAG lattice. The very low energy emission of Ce 3+ in YAG can be explained by the lowering of the lowest energy emitting 5d state of Ce 3+ by a combined effect of a large CF splitting and a high covalency.…”

Section: Resultsmentioning

confidence: 95%

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺

Ogiegło

Zych²,

Ivanovskikh³

et al. 2012

J. Phys. Chem. A

Self Cite

104

View full text Add to dashboard Cite

Lu(3)Al(5)O(12) (LuAG) doped with Ce(3+) is a promising scintillator material with a high density and a fast response time. The light output under X-ray or γ-ray excitation is, however, well below the theoretical limit. In this paper the influence of codoping with Tb(3+) is investigated with the aim to increase the light output. High resolution spectra of singly doped LuAG (with Ce(3+) or Tb(3+)) are reported and provide insight into the energy level structure of the two ions in LuAG. For Ce(3+) zero-phonon lines and vibronic structure are observed for the two lowest energy 5d bands and the Stokes' shift (2 350 cm(-1)) and Huang-Rhys coupling parameter (S = 9) have been determined. Tb(3+) 4f-5d transitions to the high spin (HS) and low spin (LS) states are observed (including a zero-phonon line and vibrational structure for the high spin state). The HS-LS splitting of 5400 cm(-1) is smaller than usually observed and is explained by a reduction of the 5d-4f exchange coupling parameter J by covalency. Upon replacing the smaller Lu(3+) ion with the larger Tb(3+) ion, the crystal field splitting for the lowest 5d states increases, causing the lowest 5d state to shift below the (5)D(4) state of Tb(3+) and allowing for efficient energy transfer from Tb(3+) to Ce(3+) down to the lowest temperatures. Luminescence decay measurements confirm efficient energy transfer from Tb(3+) to Ce(3+) and provide a qualitative understanding of the energy transfer process. Co-doping with Tb(3+) does not result in the desired increase in light output, and an explanation based on electron trapping in defects is discussed.

show abstract

Section: Resultsmentioning

confidence: 95%

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺

Ogiegło

Zych²,

Ivanovskikh³

et al. 2012

J. Phys. Chem. A

Self Cite

104

View full text Add to dashboard Cite

show abstract

“…120 The applicability of this approach is however limited since ZPLs are most often obscured in spectra of 4f-5d transitions. This is the energy which is used for constructing the energy level schemes.…”

Section: Vibronic Interactionsmentioning

confidence: 99%

Energy level modeling of lanthanide materials: review and uncertainty analysis

Joos

Poelman

Smet

2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Energy level schemes are an essential tool for the description and interpretation of atomic spectra. During the last 40 years, several empirical methods and relationships were devised for constructing energy level schemes of lanthanide defects in wide band gap solids, culminating in the chemical shift model by Thiel and Dorenbos. This model allows us to calculate the electronic and optical properties of the considered materials. However, an unbiased assessment of the accuracy of the obtained values of the calculated parameters is still lacking to a large extent. In this paper, error margins for calculated electronic and optical properties are deduced. It is found that optical transitions can be predicted within an acceptable error margin, while the description of phenomena involving conduction band states is limited to qualitative interpretation due to the large error margins for physical observables such as thermal quenching temperature, corresponding to standard deviations in the range 0.3-0.5 eV for the relevant energy differences. As an example, the electronic structure of lanthanide doped calcium thiogallate (CaGa2S4) is determined, taking the experimental spectra of CaGa2S4:Ln(Q+) (Ln(Q+) = Ce(3+), Eu(2+), Tm(3+)) as input. Two different approaches to obtain the shape of the zig-zag curves connecting the 4f levels of the different lanthanides are explored and compared.

show abstract

“…This is a direct consequence of the fact that these empirical charge-state transition level schemes do not take vibronic interactions or correlation (i.e. multiplet) effects into account [47,8]. In the case of Ce 3+ , there is a clear difference in the details of the 5d manifold for both defects.…”

Section: Also Upon Cementioning

confidence: 99%

Nonequivalent lanthanide defects: Energy level modeling

2016

View full text Add to dashboard Cite

Empirical charge-state transition level schemes are popular tools to model the properties of lanthanide-doped materials and their construction has become standard practice. Typically, it is implicitly assumed that all lanthanide ions form isostructural defects. However, in practice, multiple nonequivalent defects related to the same lanthanide can occur or different lanthanides can even incorporate in different ways. The consequences of these complications on the impurity energy levels are discussed in this article. It seems that small structural differences around the lanthanide dopant can give rise to important spectral differences in its emission. These are not always clearly reproduced by the charge-state transition level schemes. Improvements to the existing procedure are suggested and applied to the lanthanide ions in the well-studied host crystals SrAl2O4, Sr2Si5N8 and SrGa2S4.

show abstract

Analysis of the shift of zero-phonon lines for f–d luminescence of lanthanides in relation to the Dorenbos model

Cited by 14 publications

References 16 publications

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺

Energy level modeling of lanthanide materials: review and uncertainty analysis

Nonequivalent lanthanide defects: Energy level modeling

Contact Info

Product

Resources

About

Analysis of the shift of zero-phonon lines for f–d luminescence of lanthanides in relation to the Dorenbos model

Cited by 14 publications

References 16 publications

Luminescence and Energy Transfer in Lu3Al5O12 Scintillators Co-Doped with Ce3+ and Tb3+

Luminescence and Energy Transfer in Lu3Al5O12 Scintillators Co-Doped with Ce3+ and Tb3+

Energy level modeling of lanthanide materials: review and uncertainty analysis

Nonequivalent lanthanide defects: Energy level modeling

Contact Info

Product

Resources

About

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺

Luminescence and Energy Transfer in Lu₃Al₅O₁₂ Scintillators Co-Doped with Ce³⁺ and Tb³⁺