BiXO3 (X= Cr,Mn, Fe,Ni)结构稳定性的第一性原理研究

本文采用基于密度泛函理论的广义梯度近似方法和赝势平面波法的第一性原理计算及化学势的热力学平衡原理,对BiXO₃ (X= Cr, Mn, Fe, Ni)的结构稳定性进行了仔细的研究. 结果表明,这四种多铁化合物中, BiFeO₃最稳定, BiCrO₃次之, 而BiMnO3和BiNiO3则很难在热平衡条件下稳定,因此在样品制备中要多考虑热平衡之外的手段. 关键词： 3')" href="#">BiXO₃ 结构稳定性 第一性原理

Theoretical study of structural stabilities of BiXO3 (X= Cr, Mn, Fe, Ni)

The stable chemical potential phases of BiXO₃ (X= Cr, Mn, Fe, Ni) are studied by density functional theory with the consideration of thermodynamics equilibrium conditions. It is found that the BiFeO₃ and BiCrO₃ have stable chemical potential regions and are expected to be synthesized, under thermodynamic equilibrium conditions. On the contrary, no stable regions are found for BiMnO₃ and BiNiO₃, indicating that they are hard to synthesize. Therefore the approaches to their preparation under non-thermodynamic equilibrium conditions should be considered.