Infrared absorption spectroscopic study of Nd3+ substituted Zn�?�Mg ferrites

[摘要] Compositions of polycrystalline Zn_ð‘�?Mg_{1-ð‘�?}Fe_{2â€�?�ð�?��?}Nd_ð‘�?O₄ (ð‘�? = 0.00, 0.20, 0.40, 0.60, 0.80 and 1.00; ð‘�? = 0.00, 0.05 and 0.10) ferrites were prepared by standard ceramic method and characterized by X-ray diffraction, scanning electron microscopy and infrared absorption spectroscopy. Far infrared absorption spectra show two significant absorption bands, first at about 600 cm^â€�??1 and second at about 425 cm^â€�??1 , which were respectively attributed to tetrahedral (A) and octahedral (B) sites of the spinel. The positions of bands are found to be composition dependent. The force constants, $K_T$ and $K_O$, were calculated and plotted against zinc concentration. Compositional dependence of force constants is explained on the basis of cationâ€�?�oxygen bond distances of respective sites and cation distribution.

[学科分类] 材料工程

[关键词] Polycrystalline ferrites;rare earth;IR absorption;cation distribution;force constants.