Ab Initio Study of Electronic and Magnetic Structure and Structural Phase Transition of (Fe_{1 - x}Mn_x)₂P_{1 - y}Ge_yAlloys

Abstract

The paper presents results of the ab initio electronic structure calculations performed for the (Fe0.5Mn0.5)2P0.67Ge0.33 alloy, a member of (Fe1−xMnx)2P1−yGey family of alloys showing a giant magnetocaloric eect. Calculations conrmed the strong relationship between the magnetic state and crystal structure of the alloy. To investigate the isostructural phase transition driven by external magnetic eld observed in (Fe0.9Mn1.1)P0.8Ge0.2 we utilized the xed spin moment approach. Total energy analysis conrmed the occurrence of isostructural phase transition.

Substitution- and strain-induced magnetic phase transition in iron carbide

“…Ry. The FSM method [13][14][15][16] is used for the magnetic phase transition calculations, which yields the ground state of a constrained system [17]. In the FSM calculation, the value of the parameter used for the constrained magnetization was chosen as 5 Ry [24].…”

“…The occupation numbers of electrons are expressed as a Gaussian distribution function with an electronic temperature of kT = 0.001 Ry. The FSM method [13][14][15][16] is used for the magnetic phase transition calculations, which yields the ground state of a constrained system [17]. In the FSM calculation, the value of the parameter used for the constrained magnetization was chosen as 5 Ry [24].…”

“…In this study, by fixed spin -moment (FSM) calculation, we present results for the electronic structure and the magnetic phase transition with and without the strain effect in Fe 3−x Cr x C compounds, where x = 0, 1, 2, and 3 [13][14][15][16]. This computational technique allows the ground state of a constrained system [17] to be determined in the plane -wave self -consistent method within the framework of density functional theory (DFT) [18,19].…”