Local lattice relaxation around Tl substitutional impurities in a NaI(Tl) scintillator crystal
Artikel i vetenskaplig tidskrift, 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
Scintillator crystal
NaI(Tl)
Impurity site
Författare
A. Filipponi
Universita degli Studi dell'Aquila
Laboratori Nazionali del Gran Sasso
G. Profeta
Laboratori Nazionali del Gran Sasso
Universita degli Studi dell'Aquila
N. Di Marco
Gran Sasso Science Institute (GSSI)
Laboratori Nazionali del Gran Sasso
Vanessa Zema
Gran Sasso Science Institute (GSSI)
Chalmers, Fysik, Subatomär fysik och plasmafysik
K. Schäffner
Max-Planck-Gesellschaft
F. Reindl
Österreichische Akademie der Wissenschaften
Atominstitut der Osterreichischen Universitaten
Messaoud Harfouche
Next to Princess Rahma University College
A. Trapananti
Istituto Nazionale di Fisica Nucleare
Universita degli Studi di Camerino
A. Di Cicco
Universita degli Studi di Camerino
Istituto Nazionale di Fisica Nucleare
Radiation Physics and Chemistry
0969-806X (ISSN) 18790895 (eISSN)
Vol. 177 108992Ämneskategorier (SSIF 2011)
Atom- och molekylfysik och optik
Annan fysik
Den kondenserade materiens fysik
DOI
10.1016/j.radphyschem.2020.108992