M�ssbauer investigations into magnesium ferrite doped with indium and scandium ions

Magnetic study of substituted Mg–Mn ferrites synthesized by citrate precursor method

“…In 3+ ions preferentially occupy the tetrahedral site [10], Al 3+ ions have a strong affinity to occupy the octahedral site [23] and Co 2+ ions preferentially occupy B site [24] but the increase in n B with increasing substitution of Co is attributed to the high exchange interaction energy and relatively higher orbital contribution of Co for the magnetic moment. In the case of increased In 3+ substitution, as the Fe 3+ (B)/ Fe 3+ (A) ratio increases which increases saturation magnetization and therefore n B increases, but with increasing Al 3+ ions, Fe 3+ (B)/Fe 3+ (A) ratio decreases and therefore the magneton number, n B , decreases.…”

“…It has been reported that in Mg-Mn ferrite if Fe ions are replaced by In [4,9,10], Al [1,4,10] and Co [11], the magnetic properties are modified. The citrate precursor method [12][13][14][15][16] ensures ease of preparation and control of composition, particle size, purity, homogeneity and uniform grain growth.…”

Effect of In3+ ions doping on the structural and magnetic properties of Mg0.2Mn0.5Ni0.3InxFe2−xO4 spinel ferrites

“…Magnetic properties of spinel ferrite depend on distribution of cations among two sublattices, tetrahedral A-sites and octahedral B-sites [3,4]. In Mg-Mn ferrite, if Fe 3 þ ions are replaced by In 3 þ ions and Al 3 þ ions, magnetic properties are modified [5][6][7]. Synthesis of nanometersized particles proved to be one of the interesting fields of material science in material processing and technological applications, as small size particles have some of the interesting properties as compared to bulk particles [8].…”

In3+ substitution effects and defect distribution in Li0.25Mg0.5Mn0.1Fe2.15−xInxO4 studied by positron annihilation and Mössbauer spectroscopy

“…2) initially rises and then falls, owing to a reduction in the trapping sites, as more and more In 3+ ions become capable of replacing the Fe 3+ ions. It is noted from the work of Kirichok et al [5] that, even though initially In 3+ ions replace Fe 3+ ions from the tetrahedral sites, at concentrations x larger than 0.3, they replace some Fe 3+ ions at the octahedral sites as well. The present results from positron annihilation are consistent with these findings.…”

“…Its increase when In 3+ ions are doped in Li 0.25 Mg 0.5 Mn 0.1 Fe 2.15 O 4 (upto x ¼ 0:3) suggests an increase in the size of the vacancy where positrons are trapped. It has been reported[5,6] that when In 3+ ions are substituted in place of Fe 3+ ions, they preferably occupy the tetrahedral sites upto a concentration xp0:3 and then migrate towards the octahedral sites. When the In 3+ ions (of radii $0.91 Å ) try to occupy theARTICLE IN PRESS…”