Ferromagnetic-to-antiferromagnetic transition in (Hf1−xTix)Fe2 intermetallic compounds induced by geometrical frustration of the Fe(2a) sites

Reentrant spin-glass behavior induced by the frustration of Fe-Fe interactions in Laves phase Nb1−xHfxFe2 alloys

“…30 exchange bonds tend to be frustrated in the sense that they are not energetically satisfied. 31 Magnetic frustration is a familiar feature in the lattice in which magnetic atoms form a network of vertex-sharing tetrahedra.…”

Low temperature high magnetic field57Fe Mössbauer study of kinetic arrest in Ta doped HfFe2

“…Also, in contrast to bulk magnetic measurements, which essentially measure the response of the sample as a whole to the applied magnetic field, one can estimate the individual response of FM and AFM fractions to the applied magnetic field from the Mössbauer measurements as discussed below. And finally, because of polarization selection rules with the application of external magnetic fields, the Mössbauer data gives unambiguous information regarding the linearity of the magnetic structure, which is expected to give inputs to explain the magnetic phase transition as proposed by Delyagin et al [3].…”

“…Such discontinuous change in B IN T values through the FM to AFM transition is also observed in FeRh system and is explained in terms of difference of the polarization of conduction electrons to B IN T in the two states [6]. The B IN T on 6h and 2a sites of Fe in Hf 1−x T a x F e 2 compounds is of comparable value (≈17 Tesla) in FM state and it reduces drastically in AFM state (≈ 10 Tesla for 6h site and zero for 2a site of AFM phase) [1][2][3][4]. In FM Hf F e 2 , various contributions to the B IN T at both Hf and Fe sites are calculated theoretically, which are found to match excellently with the measured values and it is reported that the magnetism in Hf F e 2 originates mainly from the Fe atomic magnetism [4].…”

“…Therefore, depending on the type of R atoms, these compounds exhibit large changes in the magnetic properties with composition / temperature without any change in the crystal structure and hence, have been extensively explored [1][2][3][4]. For example, the magnetic ground state is reported to change from ferromagnetism (FM) to anti-ferromagnetism (AFM) at a Ta concentration between x=0.2 to 0.3 in Hf 1−x T a x F e 2 [2,5], whereas in Hf 1−x T i x F e 2 , this transition is reported to take place in the vicinity of x=0.6 [3]. Irrespective of magnetic ordering, the fraction of Fe occupying 6h and 2a sites is reported to be in the ratio of 3:1 from structural and Mössbauer data as well [1][2][3][4].…”

“…For example, the magnetic ground state is reported to change from ferromagnetism (FM) to anti-ferromagnetism (AFM) at a Ta concentration between x=0.2 to 0.3 in Hf 1−x T a x F e 2 [2,5], whereas in Hf 1−x T i x F e 2 , this transition is reported to take place in the vicinity of x=0.6 [3]. Irrespective of magnetic ordering, the fraction of Fe occupying 6h and 2a sites is reported to be in the ratio of 3:1 from structural and Mössbauer data as well [1][2][3][4]. Apart from the bulk magnetization measurements, these compounds were also studied by Mössbauer and perturbed angular correlation techniques to measure the hyperfine interactions in these compounds.…”