In this paper, we have used the Monte Carlo simulations (MCSs) to investigate the magnetic properties of the brownmillerite KBiFe₂O₅ (KBFO) compound. The different exchange coupling interactions J1, J2 and J3 between different irons Fe atom have been outlined including the angles between Fe₁-O-Fe₂. The double exchange interaction is caused by the existence of the oxygen atoms. In a first step, we present the ground state phase diagrams in the absence of any temperature fluctuations, in different physical parameter planes. Then we present investigation of the magnetic properties and the behavior of the total magnetizations, the total susceptibilities, as a function of temperature, crystal field, the exchange coupling interactions and the external magnetic field. Also, we provide the dependency of the total magnetizations showing the hysteresis loops of the KBFO compound, for selected values of temperature, crystal field and the exchange coupling interactions.

中文翻译：

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纳米褐煤 KBiFe2O5 的磁性：蒙特卡罗模拟

在本文中，我们使用蒙特卡罗模拟 (MCSs) 来研究褐煤 KBiFe ₂ O ₅ (KBFO) 化合物的磁性。不同的交换耦合相互作用Ĵ1,Ĵ2和Ĵ3已经概述了不同铁之间的Fe原子，包括Fe ₁ -O-Fe ₂之间的角度。双交换相互作用是由氧原子的存在引起的。第一步，我们在没有任何温度波动的情况下，在不同的物理参数平面上呈现基态相图。然后，我们研究了总磁化强度和总磁化率的磁性和行为，作为温度、晶体场、交换耦合相互作用和外部磁场的函数。此外，我们提供了总磁化强度的依赖性，显示了 KBFO 化合物的磁滞回线，用于选定的温度值、晶体场和交换耦合相互作用。