Structural and vibrational studies of NiAlxFe2−xO4 ferrites (0≤x≤1)

Cations distribution by Rietveld refinement and magnetic properties of MgCrxFe2−xO4 spinel ferrites

“…This is consistent with the decrease of the lattice constant a, as shown in Table 2, with iron substitution by chromium which could be interpreted as due to bigger size effect of Fe3+ (0.67 Å) than Cr3+ (0.64 Å). This has already been discussed in a previous publication on Mg-Cr ferrites [20] and similar behavior has been reported for mixed structure spinel Ni-Cr ferrites [24] as well as Ni-Al ferrites [26].…”

“…The starting materials were analytical reagent-grade MgO, Fe2O3 and Cr2O3 (BDH) and were weighed stoichiometrically as per chemical formula unit. The details of samples preparation are described in previous publication [26]. The single-phase spinel structure was confirmed by the X-ray diffraction spectra (XRD) of these samples obtained with a PANalytical X'Pert Pro diffractometer using CuKα radiation (i = 1.5406 Å).…”

Structural characteristics, cation distribution, and elastic properties of Cr3+ substituted stoichiometric and non-stoichiometric cobalt ferrites

“…Here, c is the velocity of light, m is the reduced mass which we have calculated by the following relation: 38,39 m ¼…”

“…Force constant according to Waldron relation: 21 k t = 4π 2 c 2 ν 1 2 μ k o = 4π 2 c 2 ν 2 2 μ k av = ( k t + k o )/2Here, c is the velocity of light, μ is the reduced mass which we have calculated by the following relation: 38,39 where m 1 is the weighted average of atomic weights of the cations residing at the A-site or B-site while m 2 is the atomic weight of oxygen anion.…”

Impact of copper immobilization on dramatic conversion of inactive NiAlFeO4 to an active catalyst for reduction of nitrophenols and a visible light photocatalyst for effective removal of organic contaminants from waste water

“…The diffraction of the ( 220), ( 311), ( 400), ( 511) or ( 333), (440), and (533) lattice planes of NAFO resulted in six characteristic peaks at 30.691, 36.271, 43.471, 57.911, 63.361, and 75.511 indicating the cubic spinel structure having space group Fd% 3m. 44 These peaks were matched with No. JCPDS#10-0325.…”