Temperature Dependence Of Magnetic Susceptibility Research Articles

Single crystal synthesis, structure, and magnetism of Pb10−xCux(PO4)6O

The recent claim of superconductivity above room temperature in Pb10−xCux(PO4)6O with 0.9 < x < 1 (referred to as LK-99) has sparked considerable interest. To minimize the influence of structural defects and impurity phases on the physical properties, we have synthesized phase-pure single crystals with a copper doping level of x ∼ 1. We find that the crystals are highly insulating and optically transparent. X-ray analysis reveals an uneven distribution of the substituted Cu throughout the sample. Temperature (T) dependent magnetic susceptibility measurements for 2 ≤ T ≤ 800 K reveal the diamagnetic response characteristic of a non-magnetic insulator, as well as a small ferromagnetic component, possibly originating from frustrated exchange interactions in Cu-rich clusters in the Pb10−xCux(PO4)6O structure. No anomalies indicative of phase transitions are observed. We, therefore, rule out the presence of superconductivity in Pb9Cu(PO4)6O crystals and provide some considerations on the origin of anomalies previously reported in experiments on polycrystalline specimens.

Temperature controlled magnon–photon coupling in a YIG/GGG-superconducting cavity coupled system

To explore potential applications in classical and quantum information transfer, the hybrid systems between yttrium iron garnet (YIG) and cavities have been extensively studied, and four coupling regimes have been defined based on the relative strength between the coupling strength and dissipation rate of each subsystem. Achieving the control of magnon–photon coupling between nano-thick YIG films and cavities remains to be explored. We experimentally measure the microwave transmission spectra of a nano-thick yttrium iron garnet/gadolinium gallium garnet (YIG/GGG) film coupled to a superconducting cavity at different temperatures. The dissipation rate of the superconducting cavity increases significantly with decreasing temperature, which is influenced by the temperature-dependent magnetic susceptibility of the GGG substrate. Accompanied by the temperature-dependent magnon dissipation rate, a continuous transformation of the coupled system in strong coupling, Purcell and weak coupling regimes is achieved.

Magnetic properties and magnetocaloric effect of a metallic triangular lattice antiferromagnetic DyAl2Ge2 single crystal

We report the synthesis, magnetic susceptibility, magnetization, electrical resistivity, heat capacity, and magnetocaloric properties of the metallic triangular lattice antiferromagnetic DyAl2Ge2 single crystal. High-quality rare-earth intermetallic compound DyAl2Ge2 single crystals were synthesized by the metallic flux method. DyAl2Ge2 crystallizes in a trigonal CaAl2Si2-type structure with Dy atoms forming a triangular lattice in the ab plane. The paramagnetic-antiferromagnetic transition occurs at 8 K, as determined by temperature dependencies of magnetic susceptibility and heat capacity. No observable hysteresis was found in the field-induced antiferromagnetic to the ferromagnetic metamagnetic transition of DyAl2Ge2. The electrical resistivity shows an overall metallic behavior with an upturn at the ordering temperature. For a magnetic field change of 0–70 kOe, the maximum magnetic-entropy change is −14.2 J kg−1 K−1 at 11 K and the relative cooling power is 327 J kg−1 with the applied magnetic field along the ab plane.

Cation exchange route to a Eu(II)-containing tantalum oxide

Traditional synthetic efforts to prepare Eu(II)-containing oxides have principally involved the use of high temperature reactions starting from EuO or a controlled, highly-reducing, atmosphere. Conversely, chimie douce approaches that are more amenable to the targeted syntheses of new, and potentially metastable, Eu(II)-oxides have yet to be explored. Herein, a cation-exchange route to new Eu(II)-containing oxides, e.g., EuTa4-xO11 (x = 0.04), has been discovered and its structure determined by powder X-ray diffraction (Space group P6322 (#182), a = 6.2539(2) Å; c = 12.3417(2) Å). The compound derives from the cation exchange of Na2Ta4O11, via a reaction with EuBr2 at 1173 K, and replacement by half the number of divalent Eu cations. Rietveld refinements show preferential ordering of the Eu cations over one of the two possible cation sites, i.e., Wyckoff site 2d (∼94%; Eu1) versus 2b (∼6%; Eu2). Total energy calculations confirm an energetic preference of the Eu cation in the 2d site. Tantalum vacancies of ∼1% occur within the layer of Eu cations and TaO6 octahedra, and ∼20% partial oxidation of Eu(II) to Eu(III) cations from charge balance considerations. 151Eu Mössbauer spectroscopy measured at 78 K found a Eu(II):Eu(III) ratio of 69:31, with a relatively broad line width of the former signal of Γ = 7.6(2) mm s–1. Also, the temperature-dependent magnetic susceptibility could be fitted to a Curie Weiss expression, giving a μeff = 6.2 μB and θCW = −10 K and confirming a mixture of Eu(II)/Eu(III) cations. The optical bandgap of EuTa4-xO11 was found to be ∼1.5 eV (indirect), significantly redshifted as compared to ∼4.1 eV for Na2Ta4O11. Spin-polarized electronic structure calculations show that this redshift stems from the addition of Eu 4f7 states as a higher-energy valence band. Thus, these results demonstrate a new cation-exchange approach that represents a useful synthetic pathway to new Eu(II)-containing oxides for tunable magnetic and optical properties.

Cementite-type Y3Ru

Abstract Single crystals of Y3Ru were obtained as a side product during phase analytical studies of yttrium-rich compounds in the system Y–Ru–Zn. The structure of Y3Ru was refined from single-crystal X-ray diffractometer data: Fe3C type, Pnma, a = 732.51(7), b = 925.61(8), c = 633.66(10) pm, wR = 0.0639, 811 F 2 values, 23 variables. The ruthenium atoms have coordination number 9 in form of a strongly distorted tricapped trigonal yttrium prism with Ru–Y distances ranging from 275–391 pm. The second substructure concerns empty Y6 octahedra (d(Y–Y) = 344–396 pm). Electronic structure calculations show a net charge transfer from yttrium to ruthenium and underpin the essentially covalent Y–Ru bonding. A phase-pure sample of Y3Ru was synthesized from the elements by arc-melting. Temperature-dependent magnetic susceptibility studies of this sample reveal Pauli paramagnetism (3.6(1) × 10−5 emu mol−1 at T = 300 K).

Temperature-Dependent Modulation of Short-Wave-Infrared Light Transparency Based on Associated Structures of a Liquescent Nickel(III) Complex.

A liquescent bis(malononitriledithiolato)nickel(III) complex with a bis(methoxyethyl)imidazolium cation, 1[Ni(mnt)2 ], exhibits three-stage thermochromic modulation of transparency/absorption in the short-wave-infrared (SWIR) region (1000-2500nm), driven by associated structural changes. Upon heating, the electronic spectra of 1[Ni(mnt)2 ] in the SWIR region shift to shorter wavelengths accompanying with the solid-liquid phase transition at 76°C. Further heating to over 109°C induces a second transition of the electronic spectra, characterized by a blue-shift of the SWIR absorption in the liquid phase. The results of temperature-dependent electronic spectra and magnetic susceptibility indicated that the thermochromic changes can be attributed to the two-step dissociation of the associated structures of [Ni(mnt)2 ]- , occurring during the solid-liquid phase transition and the shift of dimer-monomer equilibrium in the liquid state. These changes can be visualized using an SWIR imaging camera under appropriate SWIR lights.

Two-Step Magnetic Ordering in Intercalated Niobium Dichalcogenide MnXNbS2

Transition metal dichalcogenides are studied due to the possibility of creating nanoscale semiconductor devices, as well as fundamental issues of magnetic ordering. We researched the crystal structure and magnetic properties of niobium dichalcogenide Mn0.30NbS2. The results of the X-ray study showed the possible existence of an intermediate 23a0·23a0 structure between the “basic” superstructures. Also, two local maximums were found in the temperature dependence of the dynamic magnetic susceptibility. These features can indirectly confirm the presence of a transition superstructure and reflect the two-step nature of the magnetic ordering.

Desolvation-induced magnetic switching from single-ion magnetism to spin-crossover in a halogen-functionalized cobalt(II) complex

The switching between spin-crossover (SCO) and single-ion magnet (SIM) are fascinating because the process provides potential in-depth understating of different bistability. Herein, we present a rare example of the desolvation-induced magnetic switching from single-ion magnetism to SCO between a halogen-functionalized cobalt(II) complex, [Co(Brphtpy)2](PF6)2·2MeOH (Brphtpy = 4′-(4-Bromophenyl)-2,2′:6′,2′'-terpyridine, 1·2MeOH) and its desolvated material of [Co(Brphtpy)2](PF6)2 (1). The temperature-dependent magnetic susceptibility and variable-temperature single crystal X-ray diffraction results show a high spin state of the Co(II) ions in 1·2MeOH. At lower temperature, frequency- and temperature-dependent slow magnetic relaxation behaviors were evidenced under an applied dc field of 1000Oe, originating from the easy-plane magnetic anisotropy (D=43.5 cm−1) of Co(II) ions. After the release of methanol molecules, interestingly, the desovated material 1 display a complete and cooperative two-step spin transitions with transition temperatures being 350 and 125K. Differential scanning calorimetry measurements support the stepwise SCO behavior and reveal the related ΔH and ΔS.

The significant magnetic attenuation with submicrometer scale magnetic phase separation in tensile-strained LaCoO3 films

It is well known that the epitaxial strain plays a vital role in tuning the magnetic states in transition metal oxide LaCoO3 films. Here, we reported a robust long-range ferromagnetic (FM) ground state in a tensile-strained perovskite LaCoO3 film on a SrTiO3 (STO) substrate, which has a very significant attenuation when the thickness ranges from 10 to 50 nm. It is speculated that such attenuation may be caused by the appearance of the cross-hatched grain boundary, which relaxes the tensile strain around the crosshatch, resulting in the local non-FM phases. Magnetic force microscope observation reveals non-FM patterns correlated with the structural crosshatches in the strain-relaxed film even down to a temperature of 2 K and up to a magnetic field of 7 T, suggesting the phase separation origin of magnetization attenuation. Furthermore, the investigations of the temperature-dependent inverse magnetic susceptibility show a deviation from the Curie–Weiss law above the transition temperature in a 50-nm-thick LaCoO3/STO film but not in the LaCoO3/LaAlO3 film, which is ascribed to the Griffiths phase due to the crosshatch-line grain boundaries. These results demonstrated that the local strain effect due to structural defects is important to affect the ferromagnetism in strain-engineered LaCoO3 films, which may have potential implications for future oxide-based spintronics.

Transverse expansion of Bjorken flow in (1+1D) relativistic ideal-magnetohydrodynamics with magnetization

We study the evolution of magnetized quark gluon plasma (QGP) in the magneto hydrodynamic (MHD) framework. The fluid under investigation has a non-zero magnetization with infinite electrical conductivity. We solve the coupled Maxwell and conservation equations in (1+1D) transverse flow. We assume that the motion of fluid is longitudinally boost-invariant along beam line.In this study, we consider two different scenarios. First, we consider an ideal relativistic plasma with massless particles and infinite electrical conductivity with a constant magnetic susceptibility (χm). Thus, we solve the coupled Maxwell and conservation equations, and obtain the transverse fluid velocity, the energy density and the magnetic field as functions of both space and time. We investigate the effects of magnetic susceptibility (χm) on the evolution of thermodynamic quantities. Then, we solve the coupled Maxwell and conservation equations with a temperature-dependent magnetic susceptibility and a realistic equation of state given by lattice-QCD data [43,44]. We find the evaluation of temperature, energy density, the magnetic field, and the transverse fluid velocity. We improve our previous study [21] to include a nonzero magnetization, the transverse relativistic velocity ux2≠0, and a realistic equation of state.We realize the effects of non-zero magnetization on the fluid quantities are rather small. Besides, our work shows a fluid with a realistic equation and a temperature-dependent magnetic susceptibility behaves like a conformal fluid with a small constant magnetic susceptibility.

Synthesis and characterization of phenoxy-bridged copper(II) complexes: Structural features, magnetic, thermal and redox properties, and theoretical studies

Three phenoxy-bridged Cu(II) complexes, atrinuclear partial cubane type Cu(II) complex [Cu3(L1)3(µ3-OH)](ClO4)2 (1) (where L1H = (E)-2-(((2-aminoethyl)imino)methyl)-5-(diethylamino) phenol) and two dinuclear Cu(II) complexes, [Cu(L2)(MeOH)(OMe)]2 (2)and [Cu(sal)(bipy)(ClO4)]2 (3) (where L2H = (E)-N'-(5-bromo-2-hydroxybenzylidene) benzohydrazide), sal = 5-Bromo salicylaldehyde, bipy = 2,2-Bipyridine) were synthesized via in-situ reaction and have been successfully characterized both experimentally and computationally. In an in-situ reaction, the Schiff base formed (L1H/L2H) behaves as tridentate ligands having ONO donor sites. The structures of Cu(II) complexes(1)-(3)were established by X-ray crystallography. In the trinuclear Cu(II) complex(1), the three phenoxy oxygen atoms of ligand L1 bridge the Cu(II) center ions in µ3-fashion, while in dinuclear Cu(II) complexes (2)and(3), the phenoxy oxygen bridges the Cu(II) center ionsin µ2-fashion. The temperature dependence magnetic susceptibility, thermal gravimetric analysis (TGA) and cyclic voltammetry analysis were performed for Cu(II) complexes(1)-(3). Hirshfeld surface analysis and 2D fingerprint plots have also been explored in the crystal structure of complexes.

Concentration transition in Cu2(Mn,Ga)BO5 solid solutions

The effects related to the conversion of magnetic structures of a Cu2MnBO5 ferrimagnet to a Cu2GaBO5 antiferromagnet under the Mn3+ → Ga3+ substitution were studied. The properties of four single crystal samples with the gallium concentration x = 0.04, 0.11, 0.17, 0.25 were examined. The chemical composition and valence state of the samples were determined by X-ray absorption spectroscopy element-sensitive technique. Distribution of the 3d metal ions over crystallographic positions was studied using the first principle calculations by Wien2k program. The evolution of the magnetic properties was investigated by the measurements of the temperature and field dependences of magnetization, dc and ac magnetic susceptibility. In agreement with the previous study of the structure evolution of Cu2Mn1-xGaxBO5 solid solutions, the critical concentration upon a change in the magnetic ordering type was found in the range x = 0.17–0.25. The non-monotonic behavior of magnetization in terms of the gallium content was found in the concentration range of 0.04–0.17. A complex pattern of magnetic phase transitions belonging to the concentration phase boundary was obtained in the compounds with gallium being within the range x = 0.17–0.25. One could observe the splitting of the peaks of the real part of ac-susceptibility of the high-temperature phase transition in the Cu2MnBO5-like phase (x = 0.04, 0.11) and that of the low-temperature one at the concentration boundary (x = 0.17, 0.25) with different frequency and orientational dependence. The type and origin of the multiple phase transitions observed in the studied samples were analyzed.

(Ca0.95Cd0.10)Pd2Cd3, SrPd2Cd3 and (Eu0.95Cd0.10)Pd2Cd3 with YNi2Al3 type structure – crystal chemistry and magnetic hyperfine interactions

Abstract The intermetallic compounds (Ca0.95Cd0.10)Pd2Cd3, SrPd2Cd3 and (Eu0.95Cd0.10)Pd2Cd3 were synthesized from the elements in sealed niobium ampoules in an induction furnace. The polycrystalline samples were characterized through their Guinier powder patterns. The structures were refined from single crystal X-ray diffractometer data: YNi2Al3 type, P6/mmm, a = 984.61(5), c = 455.33(3) pm, wR2 = 0.0216, 376 F 2 values, 21 variables for (Ca0.95Cd0.10)Pd2Cd3, a = 998.55(8), c = 453.65(3) pm, wR2 = 0.0296, 341 F 2 values, 17 variables for SrPd2Cd3 and a = 992.57(4), c = 457.34(2) pm, wR2 = 0.0300, 384 F 2 values, 21 variables for (Eu0.95Cd0.10)Pd2Cd3. The striking crystal chemical motif in the three structures is a planar [PdCd2] Kagome-type layer. The two crystallographically independent Ca (Sr, Eu) atoms have a coordination number of 18 by 6 Pd and 12 Cd atoms. The calcium and europium compound show a small degree of Ca (Eu) substitution by Cd2 dumb-bells with 281 pm Cd–Cd in (Eu0.95Cd0.10)Pd2Cd3. Temperature dependent magnetic susceptibility measurements show Curie–Weiss behaviour (7.63(1) µB/Eu atom) for the europium compound and the onset of ferromagnetic ordering at T C = 14.9(2) K. The divalent character of europium is corroborated by 151Eu Mössbauer spectroscpy.

Phase transitions in chiral ferromagnets with topological features of electronic structure (on the example of MnSi)

Magnetic and topological electronic (TEP) phase transitions in chiral ferromagnets with the Dzyaloshinskii-Moriya (DM) interaction are considered. We consider the example of a chiral helical ferromagnet MnSi with a large Berry curvature of the Fermi surface. It is shown that the state of the spin subsystem with a ferromagnetic short-range order and with Berry phases arises as a result of a first-order transition from a helicoidal ferromagnetic phase with increasing temperature. This state is characterized by left-handed vortex microstructures and manifests itself through the topological Hall effect. In the region of the paramagnetic short-range order, vortex microstructures of both signs of spin chirality arise, which leads to the experimentally observed pattern of partial chirality. With an increase in temperature, TEP appears in the chiral paramagnetic state due to that the chemical potential leaves the region of the electronic spectrum with Berry curvature. As a result, the local magnetization and chiral interaction of the DM disappear. A quantitative agreement has been obtained between the calculations of the temperature dependence of the spin magnetic susceptibility and experimental data.

Peak-ring magnetism: Rock and mineral magnetic properties of the Chicxulub impact crater

The Chicxulub impact event at ca. 66 Ma left in its wake the only complex crater on Earth with a preserved peak ring, characterized by a well-developed magnetic anomaly low. To date, little is known about its magnetic properties. The joint Integrated Ocean Drilling Program (IODP) and International Continental Scientific Drilling Program (ICDP) Expedition 364 drill core M0077A revealed that the peak ring consists of uplifted and strongly deformed granitoid basement rocks overlain by a 130-m-thick impact melt and suevite layer. Pre- and postimpact hydrothermal systems affected this basement with maximum temperatures up to 450 °C. We used microscopy, mineral chemistry, temperature-dependent magnetic susceptibility, and hysteresis properties to characterize the magnetic mineralogy of pre-, syn-, and postimpact rocks. Compared to its amount of pure, stoichiometric shocked magnetite, the granitoid basement shows low magnetic susceptibility, which is in line with earlier experimental studies indicating that shock reduces magnetic susceptibility. Cation-substituted magnetite with varying compositions in the melt rocks carries a higher induced and remanent magnetization compared to the basement. In the granitoid basement, magnetite was partially oxidized to hematite by a pre-impact hydrothermal event, but at lithological contacts with high-temperature impact melt rock, this hematite was locally retransformed back to magnetite. Elsewhere in the granitoid basement, the temperature reached in the hydrothermal system was too low for hematite retransformation. It was also too low to anneal all the lattice defects in the shocked magnetite, which likely occurs above 540 °C. The presence of shocked magnetite in the granitoid basement well explains the magnetic anomaly low due to its unusually low induced magnetization.

Magnetic Dilution as a Direct Method for Detecting and Evaluation of Exchange Interactions between Rare Earth Elements in Oxide Systems

This work is devoted to the study of exchange interactions between rare earth atoms in the LaAlO3 matrix. Using the magnetic dilution method, the study of concentration and temperature dependences of magnetic susceptibility and effective magnetic moments of diluted solid solutions the magnetic characteristics of single rare earth atoms and the character of superexchange between them are described—antiferromagnetic at low concentrations, and for samarium, predominantly ferromagnetic within greater clusters as the concentration increases. The development of superexchange is similar to the exchange between d-elements in the same matrix.

Evidence of Long-Range and Short-Range Magnetic Ordering in the Honeycomb Na3Mn2SbO6 Oxide

We present a comprehensive study of the synthesis, structure, and magnetic properties of the honeycomb oxide Na3Mn2SbO6 supported by neutron diffraction, heat capacity, and magnetization measurements. The refinements of the neutron diffraction patterns (150, 50, and 45 K) using the Rietveld method confirm the monoclinic (S. G. C2/m) structure. Temperature-dependent magnetic susceptibilities measured at varying fields along with the heat capacity measurements demonstrate the coexistence of long-range ordering (∼42 K) and short-range ordering (∼65 K). The field-dependent isothermal magnetization measurements at 5 K indicate a spin-flop transition around 5 T. Rietveld refinements of the low-temperature (below 45 K) neutron diffraction data further confirm the long-range magnetic ordering. In addition, the temperature variation of the lattice parameters obtained from the neutron powder diffraction analysis exhibited a distinct anomaly near the antiferromagnetic transition temperature. The appearance of the concomitant broadened backgrounds in the neutron powder diffraction data collected at 80, 50, and 45 K supports the short-range ordering. The resultant magnetic structure consists of spins that are aligned antiparallel with the nearest neighbors and also with the spins of the adjacent honeycomb layers. The occurrence of a fully ordered magnetic ground state (Neel antiferromagnetic (AFM)) in Na3Mn2SbO6 consolidates the significance of fabricating new honeycomb oxides.

Sublattice-Dependent Antiferromagnetic Transitions in Rare Earth Nickelates.

Perovskite rare earth nickelates exhibit remarkably rich physics in their metal-insulator and antiferromagnetic transitions, and there has been a long-standing debate on whether their magnetic structures are collinear or noncollinear. Through symmetry consideration based on the Landau theory, we discover that the antiferromagnetic transitions on the two nonequivalent Ni sublattices occur separately at different Néel temperatures induced by the O breathing mode. It is manifested by two kinks on the temperature-dependent magnetic susceptibilities with the secondary kink being continuous in the collinear magnetic structure but discontinuous in the noncollinear one. The prediction on the secondary discontinuous kink is corroborated by an existing magnetic susceptibility measurement on bulk single-crystalline nickelates, thus strongly supporting the noncollinear nature of the magnetic structure in bulk nickelates, thereby shedding new light on the long-standing debate.

Electron-Rich MoIV 3 -Polyoxomolybdates Resembling the Paratungstic Archetype.

The first polyoxometalates (POMs) composed of MoIV , MoV 2 , discrete d1 -MoV and MoVI , [MoIV 3 MoV 6 MoVI 4 O32 (μ2 -OH)(μ3 -OH)py9 ] (1), was prepared from the solvothermal partial oxidation of [MoIV 3 O2 (O2 CCH3 )6 (H2 O)3 ]ZnCl4 in a mixture of pyridine and water. The MoV =O adduct-free unit [H2 Mo12 O33 py9 ] presents the 11e-reduced Mo derivative of the paratungtic archetype. The use of methanol, ethanol, n-propyl alcohol and triglycol instead of water produced the isostructural [MoIV 3 MoV 6 MoVI 4 O32 (μ3 -OH)(μ2 -OR)py9 ](R=CH3 , 2; C2 H5 , 3; C3 H7 , 4; C2 H4 OH, 5), providing the first examples of MoIV 3 -POMs containing bridging alkoxyl groups. The addition of [CrIII Mo6 O24 ]9- led to the substitution of {MoV =O}3+ with {CrIII -py}3+ in the allomer [MoIV 3 MoV 5 MoVI 4 CrIII O32 (μ-OH)2 py10 ] (6). Using a mixture of Mo3 and MoW2 precursors afforded WVI -incorporated allomer [MoIV 3 MoV 6 MoVI WVI 3 O32 (μ-OH)2 py9 ] (7). The complete substitution of MoVI with WVI by using a mixture of the Mo2 W, MoW2 and W3 precursors produced the diamagnetic [MoIV 3 MoV 6 WVI 4 O33 (μ3 -OH)py9 ]- (syn-8) resulting from the anti→syn conversion between the top and bottom M3 triads concomitant with MoV -MoV bonding. Both anti-1-7 and syn-8 have been characterized by X-ray single crystal structural analyses. The spin distribution and magnetic interactions have been investigated by temperature-dependent magnetic susceptibility and DFT theoretical calculations. Heterogeneous hydrogen transfer catalysis has been examined by the Lewis catalysis field (LCF) theory.

A deep investigation of NiO and MnO through the first principle calculations and Monte Carlo simulations

In this study, we use Hubbard-corrected density functional theory (DFT+U) to derive spin model Hamiltonians consisting of Heisenberg exchange interactions up to the fourth nearest neighbors and bi-quadratic interactions. We map the DFT+U results of several magnetic configurations to the Heisenberg spin model Hamiltonian to estimate Heisenberg exchanges. We demonstrate that the number of magnetic configurations should be at least twice the number of exchange parameters to estimate exchange parameters correctly. To calculate biquadratic interaction, we propose specific non-collinear magnetic configurations that do not change the energy of the Heisenberg spin model. We use classical Monte Carlo (MC) simulations to evaluate DFT+U results. We obtain the temperature dependence of magnetic susceptibility and specific heat to determine the Curie–Weiss and Néel temperatures. The MC simulations reveal that although the biquadratic interaction can not change the Néel temperature, it modifies the order parameter. We indicate that for a fair comparison between classical MC simulations and experiments, we need to consider the quantum effect by applying correction in classical MC simulations.