skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent Halides AB 2 I 5 : Eu 2 + ( A = Li Cs ; B = Sr , Ba)

Abstract

Several rare-earth-doped, heavy-metal halides have recently been identified as potential next-generation luminescent materials with high efficiency at low cost. AB 2I 5:Eu 2+ (A=Li–Cs; B=Sr, Ba) is one such family of halides. Its members, such as CsBa 2I 5:Eu 2+ and KSr 2I 5:Eu 2+, are currently being investigated as high-performance scintillators with improved sensitivity, light yield, and energy resolution less than 3% at 662 keV. Within the AB 2I 5 family, our first-principles-based calculations reveal two remarkably different trends in Eu site occupation. The substitutional Eu ions occupy both eightfold-coordinated B1(VIII) and the sevenfold-coordinated B2(VII) sites in the Sr-containing compounds. However, in the Ba-containing crystals, Eu ions strongly prefer the B2(VII)sites. This random versus preferential distribution of Eu affects their electronic properties. The calculations also suggest that in the Ba-containing compounds one can expect the formation of Eu-rich domains. These results provide atomistic insight into recent experimental observations about the concentration and temperature effects in Eu-doped CsBa 2I 5. We discuss the implications of our results with respect to luminescent properties and applications. We also hypothesize Sr, Ba-mixed quaternary iodides ABa VIIISr VIII 5:Eu as scintillators having enhanced homogeneity and electronic properties.

Authors:
 [1];  [1]
  1. Arkansas State Univ., Jonesboro, AR (United States)
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1201007
Grant/Contract Number:  
ECCS-1348341; AC52-06NA25946
Resource Type:
Publisher's Accepted Manuscript
Journal Name:
Physical Review Applied
Additional Journal Information:
Journal Name: Physical Review Applied Journal Volume: 4 Journal Issue: 1; Journal ID: ISSN 2331-7019
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Fang, C.  M., and Biswas, Koushik. Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent HalidesAB2I5:Eu2+(A=Li–Cs;B=Sr, Ba). United States: N. p., 2015. Web. doi:10.1103/PhysRevApplied.4.014012.
Fang, C.  M., & Biswas, Koushik. Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent HalidesAB2I5:Eu2+(A=Li–Cs;B=Sr, Ba). United States. doi:10.1103/PhysRevApplied.4.014012.
Fang, C.  M., and Biswas, Koushik. Wed . "Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent HalidesAB2I5:Eu2+(A=Li–Cs;B=Sr, Ba)". United States. doi:10.1103/PhysRevApplied.4.014012.
@article{osti_1201007,
title = {Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent HalidesAB2I5:Eu2+(A=Li–Cs;B=Sr, Ba)},
author = {Fang, C.  M. and Biswas, Koushik},
abstractNote = {Several rare-earth-doped, heavy-metal halides have recently been identified as potential next-generation luminescent materials with high efficiency at low cost. AB2I5:Eu2+ (A=Li–Cs; B=Sr, Ba) is one such family of halides. Its members, such as CsBa2I5:Eu2+ and KSr2I5:Eu2+, are currently being investigated as high-performance scintillators with improved sensitivity, light yield, and energy resolution less than 3% at 662 keV. Within the AB2I5 family, our first-principles-based calculations reveal two remarkably different trends in Eu site occupation. The substitutional Eu ions occupy both eightfold-coordinated B1(VIII) and the sevenfold-coordinated B2(VII) sites in the Sr-containing compounds. However, in the Ba-containing crystals, Eu ions strongly prefer the B2(VII)sites. This random versus preferential distribution of Eu affects their electronic properties. The calculations also suggest that in the Ba-containing compounds one can expect the formation of Eu-rich domains. These results provide atomistic insight into recent experimental observations about the concentration and temperature effects in Eu-doped CsBa2I5. We discuss the implications of our results with respect to luminescent properties and applications. We also hypothesize Sr, Ba-mixed quaternary iodides ABaVIIISrVIII5:Eu as scintillators having enhanced homogeneity and electronic properties.},
doi = {10.1103/PhysRevApplied.4.014012},
journal = {Physical Review Applied},
number = 1,
volume = 4,
place = {United States},
year = {2015},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: 10.1103/PhysRevApplied.4.014012

Citation Metrics:
Cited by: 8 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Generalized Gradient Approximation Made Simple
journal, October 1996

  • Perdew, John P.; Burke, Kieron; Ernzerhof, Matthias
  • Physical Review Letters, Vol. 77, Issue 18, p. 3865-3868
  • DOI: 10.1103/PhysRevLett.77.3865

High-energy-resolution scintillator: Ce3+ activated LaBr3
journal, September 2001

  • van Loef, E. V. D.; Dorenbos, P.; van Eijk, C. W. E.
  • Applied Physics Letters, Vol. 79, Issue 10, p. 1573-1575
  • DOI: 10.1063/1.1385342

Projector augmented-wave method
journal, December 1994


Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
journal, July 1996


Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides
journal, September 1976


Special points for Brillouin-zone integrations
journal, June 1976

  • Monkhorst, Hendrik J.; Pack, James D.
  • Physical Review B, Vol. 13, Issue 12, p. 5188-5192
  • DOI: 10.1103/PhysRevB.13.5188

From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999


Strontium and barium iodide high light yield scintillators
journal, February 2008

  • Cherepy, Nerine J.; Hull, Giulia; Drobshoff, Alexander D.
  • Applied Physics Letters, Vol. 92, Issue 8, Article No. 083508
  • DOI: 10.1063/1.2885728

Ab initio molecular-dynamics simulation of the liquid-metal�amorphous-semiconductor transition in germanium
journal, May 1994


Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study
journal, January 1998

  • Dudarev, S. L.; Botton, G. A.; Savrasov, S. Y.
  • Physical Review B, Vol. 57, Issue 3, p. 1505-1509
  • DOI: 10.1103/PhysRevB.57.1505

Eu2+-doped Ba2CsI5, a new high-performance scintillator
journal, December 2009

  • Bourret-Courchesne, E. D.; Bizarri, G.; Borade, R.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 612, Issue 1, p. 138-142
  • DOI: 10.1016/j.nima.2009.10.146