Revisiting the magnetic and magnetocaloric properties of bulk gadolinium: A combined DFT and Monte Carlo simulations

Abstract

In this paper, a combination of DFT study and Monte Carlo (MC) simulations has been performed on Gd compound which undergoes a second–order phase transition from ferromagnetic state to paramagnetic one. For this single material, the temperature-dependent total magnetization and magnetic susceptibility have been calculated and are revealed that the Curie temperature is acceptable concurrence with the experimental value. Furthermore, it was showed that under an external magnetic field of 2 Tesla (T), MCE of Gd compound around its Curie point in regard to the maximum value of magnetic entropy change ( ), agrees well with the experimental one. Besides, the Relative Cooling Power (RCP) values are found to be 34.37, 69.18, 90.74 and 128 J.kg−1 under different magnetic fields of 0.5, 1.0, 1.5 and 2T, respectively. All findings which are presented here indicate that DFT calculations and Monte Carlo simulations can be efficiently used to predict the magnetic and magnetocaloric features of Gd and related alloys.

Calculated properties of GdNi intermetallic compound for the nitrogen liquefaction process: insight into ab-initio computations and Monte Carlo simulation

“…-DS , mag Max is found to be 17,13 JKg −1 K −1 at 5 T, which is consistent with that obtained experimentally (17.3JKg −1 K −1 , 17JKg −1 K −1 ) [16,35]. This good agreement has been often found for different materials using ab-initio calculations and MC simulation [30,36].…”

“…In the case of the ferromagnetic material with all lattice sites equivalent, the Mean-Field Approximation (MFA) method gives the relationship between the exchange coupling interaction parameters and T c (K) by applying the equation [30]:…”

“…This parameter is typically known to be a compromise between the magnitude of the magnetic entropy change and the width of the peak. Thus, its formula is given by the following equation [30]:…”

Co-, Fe-, Ni-doped and co-doped rutile GeO2: insights from ab-initio calculations

“…We used the ab-initio calculation method based on DFT and the Akai-KKR (Machikaneyama 2002) code [34] to investigate the effects of magnetic impurity (Co and Fe) doping and co-doping on the behavior of a rutile GeO 2 semiconductor. This method has given results that converge with those experimentally obtained [35][36][37][38][39][40]. Here, the doping elements will replace germanium ions in the crystal structure of the semiconductor.…”

Gadolinium-Oxide Nanoparticles for Cryogenic Magnetocaloric Applications

“…This is in fact observed in nаnopаrtіcles wіth lаrge magnetic moments of individual atoms which may easily and coherently chаnge theіr аlіgnment even upon the application of a low magnetic eld. Several compounds, pаrtіculаrly those bаsed on gаdolіnіum, are therefore currently under investigation as promising candidates for sіgnіfіcаnt MCE promotion [7][8][9][10] .…”