Local lattice relaxation around Tl substitutional impurities in a NaI(Tl) scintillator crystal
Journal article, 2020

A Thallium (Tl) L3-edge x-ray absorption experiment was performed on a NaI(Tl) scintillation crystal at room temperature using fluorescence detection. The data analysis provides clear evidence for a ≃5 % average bond length expansion of the first shell I atoms surrounding the Tl impurities with respect to the Na-I crystallographic bond-length. Possible evidence for a slight expansion of the second and third shells is obtained. The data are compatible with a previous experiment performed at liquid nitrogen temperature considering thermal expansion. A critical review of existing theoretical predictions and density functional theory supercell calculations support present findings and suggest the opportunity to perform a high quality temperature dependent experiment.

XAFS

Impurity site

NaI(Tl)

Scintillator crystal

Author

A. Filipponi

Laboratori Nazionali del Gran Sasso

University of L'Aquila

G. Profeta

University of L'Aquila

Laboratori Nazionali del Gran Sasso

N. Di Marco

Laboratori Nazionali del Gran Sasso

Gran Sasso Science Institute (GSSI)

Vanessa Zema

Gran Sasso Science Institute (GSSI)

Chalmers, Physics, Subatomic and Plasma Physics

K. Schäffner

Max Planck Society

F. Reindl

Osterreichische Akademie Der Wissenschaften

Atominstitut der Osterreichischen Universitaten

Messaoud Harfouche

Next to Princess Rahma University College

A. Trapananti

National Institute for Nuclear Physics

University of Camerino

A. Di Cicco

National Institute for Nuclear Physics

University of Camerino

Radiation Physics and Chemistry

0969-806X (ISSN) 18790895 (eISSN)

Vol. 177 108992

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Condensed Matter Physics

DOI

10.1016/j.radphyschem.2020.108992

More information

Latest update

10/12/2020