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Updated: May 6, 2026

Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Off-center Tl and Na dopant centers in CsI
R M Van Ginhoven1, P A Schultz
1Pacific Northwest National Laboratory, Richland, WA 99352, USA.
Abstract:
We use density functional theory calculations to characterize the electronic and structural properties of the Tl and Na dopant centers in CsI. We find that the Tl and Na centers can accept one or two electrons and couple to long-range relaxations in the surrounding crystal lattice to distort strongly off-center to multiple distinct minima, even without a triplet excitation. The long-range distortions are a mechanism to couple to phonon modes in the crystal, and are expected to play an important role in the phonon-assisted transport of polarons in activated CsI and subsequent light emission in this scintillator.
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