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Updated: May 19, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Isotopic phonon effects in LaB6-LaB6 do not possess cubic symmetry and show a non-random isotope distribution
H Werheit1, V Filipov, N Shitsevalova
1Institute of Physics, University Duisburg-Essen, Duisburg, Germany. helmut.werheit@uni-duisburg-essen.de
Abstract:
The isotopic phonon effects in LaB(6) are investigated on the Raman spectra of a series of high-quality single crystals with systematically varied contents of (10)B and (11)B isotopes. A detailed group theoretical analysis enlightens the correlation between distortions of the B(6) octahedra and the splitting or broadening of phonon modes. It is evident that LaB(6) does not have cubic symmetry as assumed so far. A further symmetry reduction of the B(6) octahedra occurs in isotopically mixed crystals. There, the distribution of isotopes is not random as commonly assumed; the probability of associating equal isotopes increases with their mass decreasing.
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