Structural, electronic, magnetic, half-metallic, mechanical, and thermodynamic properties of the quaternary Heusler compound FeCrRuSi: A first-principles study

Abstract

In this paper, we have investigated the structural, electronic, magnetic, half-metallic, mechanical, and thermodynamic properties of the equiatomic quaternary Heusler (EQH) compound FeCrRuSi using the density functional theory (DFT) and the quasi-harmonic Debye model. Our results reveal that FeCrRuSi is a half-metallic material (HMM) with a total magnetic moment of 2.0 μB in agreement with the well-known Slater-Pauling rule Mt = Zt − 24. Furthermore, the origin of the half-metallic band gap in FeCrRuSi is well studied through a schematic diagram of the possible d-d hybridization between Fe, Cr and Ru elements. The half-metallic behavior of FeCrRuSi can be maintained in a relatively wide range of variations of the lattice constant (5.5–5.8 Å) under uniform strain and the c/a ratio (0.96–1.05) under tetragonal distortion. The calculated phonon dispersion, cohesive and formation energies, and mechanical properties reveal that FeCrRuSi is stable with an EQH structure. Importantly, the compound of interest has been prepared and is found to exist in an EQH type structure with the presence of some B2 disorder. Moreover, the thermodynamic properties, such as the thermal expansion coefficient α, the heat capacity CV, the Grüneisen constant γ, and the Debye temperature ΘD are calculated.

Theoretical Study of the Electronic, Magnetic, Mechanical and Thermodynamic Properties of the Spin Gapless Semiconductor CoFeMnSi

“…In this section, we discuss the mechanical behavior and dynamic stability of CoFeMnSi. Only three independent elastic constants exist for a simple cubic structure and they are C 11 , C 12 and C 44 , in which C 12 and C 44 reflect the elasticity in terms of the shape and C 11 characterizes the elasticity in terms of the length [29,30,46,47]. All these elastic constants for CoFeMnSi have been calculated with the stress-strain method [36] and the derived values for CoFeMnSi are summarized in Table 2.…”

“…With one transition metal-element X-replaced by another transition metal-element X´-the ternary full-Heusler compounds transform into equiatomic quaternary Heusler (EQH) compounds with a change in the general formula to XX´YZ [26]. The EQH compounds have a stoichiometry of 1: 1: 1: 1 and thus, the structures are less disordered [23,[27][28][29][30]. Because the Mn-based and Co-based ternary Heusler materials have been investigated in numerous studies, the EQH compounds composed of Co and Mn atoms are of great interest and they can be regarded as the intermediate product of Co 2 YZ and Fe 2 YZ.…”

Structural configuration and tetragonal phase stability in the equiatomic quaternary Heusler compound TiZnMnSi

“…The family of Heusler materials stand out as one of the most promising candidates due to their excellent electronic and magnetic characteristics, such as, high Curie temperature, compatible crystal structure and tuneable properties. Initially, Heusler compounds have two typical classes: [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] half-Heusler with generic chemical formula XYZ and full-Heusler with formula X 2 YZ, where X and Y represent the transition metal elements and Z is from the main group elements. Despite the different stoichiometric ratios in these two Heusler kinds, there are always three elements in both of them and thus they can be regarded as ternary compounds.…”

Structural, Electronic, Magnetic, Mechanic and Thermodynamic Properties of the Inverse Heusler Alloy Ti2NiIn Under Pressure

“…The electronic structure of HMMs shows metallic behavior with no band gap for one channel and semiconducting behavior with band gap in the other channel, leading to a possible 100% spin polarization of electrons near the Fermi energy level [4,5]. Among these materials, the Heusler alloy family stands out because of its high Curie temperature and tunable physical properties [6][7][8]. Besides, the Heusler materials have comparable crystal structure with zinc-blende-type and rock-salt-type semiconductors [9][10][11], making them suitable for the spin injection source of semiconductors.…”