Temperature dependence of Raman spectra in the mixed system KNO2-NaNO2

Abstract

The temperature dependence of Raman bands due to internal nodes has been observed on samples with various mixture ratios of NaNO2 and KNO2. The band assigned to the bending mode of NaNO2 shifts to a lower frequency and decreases in intensity as temperature increases. The temperature dependence of frequency shift of the bending mode of KNO2 becomes noticeable with increasing mole fraction of NaNO2. The half-width of the stretching mode increases when the ferroelectric phase transition is approached.