FT-IR Studies of Nickel Substituted Polycrystalline Zinc Spinel Ferrites for Structural and Vibrational Investigations

Abstract

FT-IR spectra of Ni 1-s Zn s Fe 2 O 4 spinel ferrite, s changed by 0.2 according to 0.0 ≤ s ≤1.0, have been analyzed in the frequency range (350−1000) cm -1 . Six polycrystalline ferrites samples were synthesized using the conventional standard double sintering ceramic method. Two main absorption bands were observed, their positions were found to be strongly dependent on s-value. The high frequency band in the range 550-600 cm −1 and a low frequency band at around 400 cm −1 were assigned to tetrahedral T d and octahedral O h sites, respectively, of spinel lattice. Force constant (F C ) was calculated for T d and O h sites and was found to decrease with increasing Zn ions. Threshold frequency ν th for the electronic transition was determined and found to increase with increasing Zn ions. Cations distribution for the prepared mixed ferrite was concluded based on the FT-IR spectra. The ionic radii for each site were correlated to the cations distribution of the given ferrite.