An experimental and theoretical study of crystals of calcium fluoride doped with alkali metal cations

Jacobs, P. W. M.; Ong, S.H.; Chadwick, Alan V.; Carr, V.M.

doi:10.1016/0022-4596(80)90115-2

Cited by 9 publications

(5 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results of investigations of both AHC crystals and fluor-spars [18] testify the fact that the energy of IVD reorientation is always less than the migration energy of the free anion vacancy. The value of this difference DE ¼ E 0 --E r increases sublinearly as the difference between the size of the ion radii (Dr) of the impure cation and cation of the host crystal increases.…”

Section: Ta B L E 2 Temperatures and Energies Of Reorientation Of F þmentioning

confidence: 80%

“…It is generally accepted that IVD reorientation in crystals with the fluorite structure takes place by means of jumps of anion vacancies in h100i directions along eight equivalent anion positions that surround the impure cation [16][17][18]. If the interaction between vacancies and the impure cation (Coulomb interaction and the lattice deformation around the impurity) is neglected then the energy of IVD reorientation (E r ) has to be the same as the energy of the spacial migration of the anion vacancy (E 0 ):…”

Section: Ta B L E 2 Temperatures and Energies Of Reorientation Of F þmentioning

confidence: 99%

“…Dependence of the energy of reorientation of F þ A (curves 1-3) and M þ A -centres (curves 4 and 5) on the difference in ionic radii Dr ; (1, 4) experimental data, (3) theoretical data[18], (2), (5) calculations according to Eq (5). …”

mentioning

confidence: 99%

See 2 more Smart Citations

Reorientation of MA+-Centres in CaF2:Me+Crystals

Chornyi

Kravchuk

Kachan

et al. 2001

phys. stat. sol. (b)

View full text Add to dashboard Cite

Studies of photoinductive dichroism allow to define the orientation of colour centres. The photoinductive dichroism of absorption testifies the fact that oscillators, responsible for the long-wave absorption band of M þ A -centres, are located along h100i crystallographic directions, and high-energetic oscillators, along h110i crystallographic directions. Various impurities cause unequal perturbations in the crystal lattice. The determination of the kinetic parameters of the reorientation processes in simple and complex colour centres allows establishing the structure of the aggregative centre. The size of the impurity ion influences the energy of reorientation of M þ A -centres, and this, in turn, is connected with the displacement of vacancies towards the anion sites of the crystal. It is found that the anion vacancy in M þ A -centres jumps in h110i directions, but in F þ A -centres it jumps in h100i directions. Z. P. Chornyi et al.: Reorientation of M þ A -Centres in CaF 2 : Me + Crystals

show abstract

Section: Ta B L E 2 Temperatures and Energies Of Reorientation Of F þmentioning

confidence: 80%

Section: Ta B L E 2 Temperatures and Energies Of Reorientation Of F þmentioning

confidence: 99%

See 1 more Smart Citation

Reorientation of MA+-Centres in CaF2:Me+Crystals

Chornyi

Kravchuk

Kachan

et al. 2001

phys. stat. sol. (b)

View full text Add to dashboard Cite

show abstract

“…The capture of electrons by this trap will be difficult to rerelease, which leads to a decrease in the scintillation efficiency. Based on previous report of Li + doped CaF 2 , 44 this trap is formed due to the Li + entry into the CaF 2 lattice during eutectic formation, resulting in Li + occupying the Ca 2+ lattice sites and the formation of positively charged F vacancy defects (V F • ):…”

Section: Thermoluminescence Spectramentioning

confidence: 98%

Al³⁺ Codoped LiF-CaF₂:Eu²⁺ Bright Eutectic Scintillators for Large-Area Thermal Neutron Detectors

Zhou,

Zhao,

Yao

et al. 2024

ACS Appl. Opt. Mater.

View full text Add to dashboard Cite

Eutectic scintillators with 6 Li-containing thermal neutron absorbers are capable of efficient thermal neutron detection due to lamellar or rod-like optical waveguide structures formed by directional solidification. However, developing stable and bright eutectic scintillators with excellent neutron imaging capability remains a challenge. Here, the performance parameters for the scintillator have been substantially improved by the Al 3+ codoping strategy in the LiF-CaF 2 :Eu 2+ system. Due to the Al 3+ codoping, the photoluminescence quantum yield (PLQY) is enhanced from 55% to 80%, the light yield is increased from 11,000 to 16,000 photons/thermal neutron, and the scintillation decay time is shortened by about 30 ns. It was shown that Al 3+ codoping can effectively reduce the low-frequency shallow-energy level traps. Furthermore, large-sized (50 × 50 × 1.5 mm) translucent LiF-CaF 2 :Eu 2+ , Al 3+ eutectic ceramics have been fabricated for an Anger-logic position-sensitive detector to realize two-dimensional (2D) thermal neutron detection. A codoped LiF-CaF 2 eutectic scintillator provides a ∼1 mm spatial resolution and thermal neutron detection efficiency 16% higher than that of a commercial GS20 scintillator. This research paves the way for the application of large-area eutectic scintillators for efficient thermal neutron detection.

show abstract

“…As it follows from data on the ionic conductivity study of the MeF 2 -O 2− crystals [3], theoretical investi-gation [4], as well as from own studies of TSDC [2,5] and defects induced by electron pulse irradiation [6], O 2− -ions enter into the lattice of fluorite crystals substituting the host ions. Electric charge of the impurity ion is surplus relative to the lattice and is compensated by the anionic vacancy.…”

Section: Point Defects Structure In the Mef 2 -O 2−mentioning

confidence: 99%

Control of Radiation Sensitivity of the Oxygen-Containing Fluorite Crystals

et al. 2018

View full text Add to dashboard Cite

The parameters of radiation sensitivity of the oxygen-doped fluorite crystals were calculated in a onedimensional model. The limit concentrations of the color centers as a function of the concentration of the oxygen impurity in the fluorite crystal were defined. Fluorite crystals with anti-Frenkel defects in the anion sublattice of the crystal have a specific property: the discolored after irradiation crystal being irradiated repeatedly with ionizing radiation retains the "memory" of the preceding irradiation. Using an ion chain model this paper studies under what conditions the "radiation memory" effect can arise in the MeF2-O 2− crystals as well as the extent of its contribution into the overall radiation sensitivity of the crystal.

show abstract

An experimental and theoretical study of crystals of calcium fluoride doped with alkali metal cations

Cited by 9 publications

References 17 publications

Reorientation of MA+-Centres in CaF2:Me+Crystals

Reorientation of MA+-Centres in CaF2:Me+Crystals

Al³⁺ Codoped LiF-CaF₂:Eu²⁺ Bright Eutectic Scintillators for Large-Area Thermal Neutron Detectors

Control of Radiation Sensitivity of the Oxygen-Containing Fluorite Crystals

Contact Info

Product

Resources

About

An experimental and theoretical study of crystals of calcium fluoride doped with alkali metal cations

Cited by 9 publications

References 17 publications

Reorientation of MA+-Centres in CaF2:Me+Crystals

Reorientation of MA+-Centres in CaF2:Me+Crystals

Al3+ Codoped LiF-CaF2:Eu2+ Bright Eutectic Scintillators for Large-Area Thermal Neutron Detectors

Control of Radiation Sensitivity of the Oxygen-Containing Fluorite Crystals

Contact Info

Product

Resources

About

Al³⁺ Codoped LiF-CaF₂:Eu²⁺ Bright Eutectic Scintillators for Large-Area Thermal Neutron Detectors