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A comparison is made between experimentally and theoretically obtained lifetimes of longitudinal acoustic phonons in Al₂{O}₃$, Sr${F}₂$, Ca${F}₂$, La${F}₃$, and ${α}$-quartz. Theoretical predictions based on an isotropic, dispersionless Debye solid are shown not be be consistent with most of the experimental results.
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W. E. Bron (1980) studied this question.
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