Chapter 3 Compounds of transition elements with nonmetals

From single- to double-first-order magnetic phase transition in magnetocaloric Mn1−xCrxCoGe compounds

“…7 Earlier studies on MnCoGe confirmed a martensitic structural transformation from the low-temperature orthorhombic ͑orth.͒ TiNiSi-type structure ͑space group Pnma͒ to the high-temperature hexagonal ͑hex.͒ Ni 2 In-type structure ͑space group P6 3 / mmc͒. 8,9 On heating, this transformation occurs at the structural transition temperature ͑T str ͒ ϳ 650 K. 9 In the stable orth. ground state, MnCoGe behaves like a typical ferromagnet with a second-order PM-FM transition occurring at the ordering temperature ͑T c ͒ϳ345 K, which is far below T str .…”

Tunable dimensional crossover and magnetocrystalline anisotropy in Fe2P -based alloys

“…1.051401 Transition-metal pnictide alloys based on Fe 2 P have attracted considerable attention due to the unusual sensitivity of their magnetic properties to temperature, pressure, external magnetic field, and alloying [1][2][3][4][5], as well as their possible magnetocaloric applications [1], and they have been extensively studied theoretically [6][7][8][9]. Of particular interest is the magnetocrystalline anisotropy (MCA) of Fe 2 P, which, at 2.3 MJ/m 3 , is record high at zero temperature for systems without heavy elements [10,11].…”

“…Of particular interest is the magnetocrystalline anisotropy (MCA) of Fe 2 P, which, at 2.3 MJ/m 3 , is record high at zero temperature for systems without heavy elements [10,11]. Although ferromagnetism in Fe 2 P vanishes through a first-order phase transition at T C = 216 K, this temperature can be greatly increased by alloying with Si, Ni, Co, and other easily available elements [1,2,[12][13][14]. The origin of such unusual T C sensitivity to alloying is not understood.…”

Magnetic and Structural Properties of Mn_1.8Co_0.2Sb under High Magnetic Fields

“…1,3) With increasing x, T t and T C increase and decrease, respectively. 3) This indicates that the substitution of Co for Mn contributes to the stabilization of the AFM phase and the destabilization of the FRI phase.…”

“…Mn 2 Sb with a Cu 2 Sb-type tetragonal structure (space group: P4/nmm) is ferrimagnetic (FRI) below T C ³ 550 K. 1,2) There are two crystallographically non-equivalent sites for Mn atoms, Mn1 (2a-site) and Mn2 (2c-site), which are tetrahedrally and octahedrally surrounded by Sb atoms. The Sb atom occupies at the 2c-site.…”