Optical constants and vibrational behavior of (NH 4 ) 2 ZnBr 4 crystals
作者： J. P. Srivastava , Herbert Rauh , Asita Kulshreshtha
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摘要: Far-infrared reflectivity of ammonium tetrabromozincate crystals has been measured at 300 and 105 K in the range 50–500 cm−1. The low-temperature measurements are made ferroelectric state crystal. Optical constants frequencies optical phonon modes have evaluated by means a three-parameter classical oscillator fit to data. Absorption spectra polycrystalline samples FIR NIR regions. A vibrational assignment observed is given. It suggested that transition most likely displacive type.
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