KIM, CS HA, MY KO, HM OH, YJ LEE, HS LEE, SY SUR, JC PARK, JY 2024-01-21T21:38:13Z 2024-01-21T21:38:13Z 2021-09-02 1994-05 0021-8979 https://pubs.kist.re.kr/handle/201004/145592 The mixed series CoxFe1-xCr2S4 has been studied by x-ray, Mossbauer spectroscopy, and superconducting quantum-interference device (SQUID) magnetometry. The crystal structure is found to be a cubic spinel, and the lattice constant a0 decreases linearly with increasing cobalt concentration. Mossbauer spectra of CoxFe1-xCr2S4 have been taken at various temperatures ranging from 4.2 to 300 K. The iron ions are ferrous and occupy the tetrahedral sites. The Curie temperature increases linearly with cobalt concentration, suggesting that the superexchange interaction for the Co-S-Cr link is stronger than that for the Fe-S-Cr link. Magnetic hyperfine and quadrupole interactions in Co0.9Fe0.1Cr2S4 at 4.2 K have been studied, yielding the following results: H(hf) = 80.8 kOe, 1/2e2qQ(1 + 1/3eta2)1/2 = 2.65 mm/s, theta = 15-degrees, phi = 75-degrees, and eta = 1.O. It is notable that, as the temperature decreases below the Curie temperature, quadrupole splitting increases with decreasing temperature, suggesting the presence of an electric field gradient and accompanying relaxation effects. Magnetic susceptibility measurements by SQUID magnetometry show that superexchange interactions between Fe2+ ions are ferrimagnetic. English AMER INST PHYSICS CRYSTALLOGRAPHIC AND MAGNETIC-PROPERTIES OF COXFE1-XCR2S4 Article 10.1063/1.355463 1 JOURNAL OF APPLIED PHYSICS, v.75, no.10, pp.6078 - 6080 JOURNAL OF APPLIED PHYSICS 75 10 6078 6080 N scie scopus A1994NN73400224 2-s2.0-0006170130 Physics, Applied Physics Article; Proceedings Paper FECR2S4 crystal structure curie temperature M"ossbauer spectroscopy superexchange interaction