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MgFe2O4 has been studied using M¨ossbauer spectroscopy and X-ray diffraction. The crystal was found to have an inverse cubic spinel structure with the lattice constant a0 = 8.390 ± 0.005 °A. The M¨ossbauer spectra consisted of two sets of six lines, respectively, corresponding to Fe3+ at the tetrahedral (A) and the octahedral (B) sites. The isomer shifts indicated that the valence states of the irons at both A and B sites were in ferric high-spin states. The N´eel temperature of MgFe2O4 was TN = 710 ± 3 K. The temperature dependences of the magnetic hyperfine fields at the 57Fe nuclei at the tetrahedral (A) and the octahedral (B) sites were analyzed by using the theory of ferrimagnetism. The intrasublattice A-O-B and the intersublattice A-O-A superexchange interactions of MgFe2O4 were found to be antiferromagnetic with strengths of JA.B = .10.0 ± 0.2 kB and JA.A = .0.7 ± 0.2 kB, respectively, while the intrasublattice B-O-B superexchange interaction was ferromagnetic with a strength of JB.B = 1.4 ± 0.2 kB. The Debye temperatures for the A and the B sites of MgFe2O4 were found to be A = 417 ± 5 K and B = 331 ± 5 K, respectively.' @& pH �