Magnetic order and crystal structure study of YNi4Si-type NdNi4Si

Giant magnetic coercivity in orthorhombic YNi4Si-type SmNi4Si compound

“…Below the magnetic ordering temperature, NdNi 4 Si and TbNi 4 Si exhibit the b-collinear magnetic ordering of rare earth magnetic sublattice with Cmm′m magnetic space group and wave vector K ¼[0, 0, 0] (here Cmm′m ¼{1, m x , 2 y , m z } Â {1, 1′ Â i} Â {1, 1/[1/2, 1/2, 0]}). The magnetic moments of Nd and Tb respectively reach a value of 2.37 μ B /Nd and 8.66 μ B /Tb while the magnetic moment of Ni sublattice was not observed [9,10].…”

“…The effective magnetic moment per formula unit M eff /fu ¼0.70 μ B for SmNi 4 Si is some less than the theoretical effective moment of 0.85 μ B of trivalent Sm [19]. The positive Weiss temperature suggests the dominant ferromagnetic interaction in SmNi 4 Si as observed in the YNi 4 Si-type NdNi 4 Si [9] and TbNi 4 Si [10] compounds.…”

“…The CaCu 5 -type RNi 4 Si (R¼Ce-Nd, Sm, Gd-Yb) compounds were obtained by induction melting in argon without heat treatment [3][4][5][6][7], whereas an orthorhombic derivative of CaCu 5 -type structure was observed in the YNi 4 Si-type RNi 4 Si compounds (R¼Y, La, Ce, Nd, Sm, Gd-Ho) that were prepared by arc-furnace melting with following annealing at 1070 K for 200 h in an argon and quenching in ice-cold water [8][9][10][11]. It indicates that the structural type of RNi 4 Si is determined by the conditions of melting (i.e., the alloying temperature in liquid state) and annealing.…”

“…Interestingly, the orthorhombically distorted YNi 4 Si-type {Nd, Tb}Ni 4 Si demonstrate the increasing of coercive field, when the magnetic moments of rare-earth sublattice lie in the ab-plane of crystal lattice [9,11]. It suggests that the structural distortion from the hexagonal CaCu 5 type to the orthorhombic YNi 4 Si type of compounds with such magnetic ordering is a potential route to improve their hard magnetic properties.…”

Copper-doping effects in electronic structure and spectral properties of SmNi5

“…The RNi 5 group of intermetallic compounds (where R is a rare earth) and their substitutional derivatives have been extensively studied because of a variety of interesting properties promising for practical applications, such as magnetocaloric effect, hydrogen storage capacity, magnetic anisotropy and high coercivity [1][2][3][4][5][6]. Their diverse magnetic and electronic characteristics are associated with both localized moments of R atoms and itinerant electrons of Ni atoms in hexagonal CaCu 5 -type structure.…”