The ferromagnetic (FM)-antiferromagnetic (AFM) transition is experimentally observed in Y_1-xLa_xTiO₃. The underlying microscopic mechanism for FM-AFM transition is still an open problem and far from fully understood. Here, structural, electronic and magnetic properties of Mott insulating Y_1-xLa_xTiO₃ with x = 0, 0.25, 0.5, 0.75, and 1 are studied using hybrid density functional method. Y_1-xLa_xTiO₃ stabilizes in an orthogonal perovskite structure. As x increases, the lattice parameters and unit volume almost increase linearly. Y_1-xLa_xTiO₃ is an FM insulator at x = 0 and 0.25, an A-type AFM insulator at x = 0.5 and 0.75, and a G-type AFM insulator at x = 1. A spin-glass behavior is predicted to emerge at 0.25 < x ≤ 0.5. The calculated lattice parameters, band gaps, and magnetic ground states of Y_1-xLa_xTiO₃ are in good agreement with available experimental data. The Ti–O–Ti bond angels increase with increasing x while the total energy difference between the AFM and FM states decreases and then is less than 0 meV. An FM-AFM phase transition is strongly favored with decrease of the GdFeO₃-type distortion. The present study reproduces structural, electronic and magnetic properties of Mott insulating Y_1-xLa_xTiO₃, and interprets well experimentally-observed magnetic phase transition.

在Y _1-x La _x TiO _3中实验观察到铁磁（FM）-反铁磁（AFM）跃迁。FM-AFM过渡的潜在微观机制仍然是一个悬而未决的问题，远未得到充分理解。在这里，使用混合密度泛函方法研究了x = 0、0.25、0.5、0.75和1的Mott绝缘Y _1-x La _x TiO _3的结构，电子和磁性。Y _1-x La _x TiO ₃稳定在正交钙钛矿结构中。随着x的增加，晶格参数和单位体积几乎线性增加。Y _1-x La _x TiO ₃在x = 0和0.25时是FM绝缘子，在x = 0.5和0.75时是A型AFM绝缘子，在x = 1时是G型AFM绝缘子。预计在0.25 <x≤时会出现自旋玻璃行为。 0.5。Y _1-x La _x TiO ₃的计算晶格参数，带隙和磁基态与可用的实验数据非常吻合。Ti-O-Ti键的角度随着x的增加而增加，而AFM和FM状态之间的总能量差减小，然后小于0 meV。减少GdFeO ₃型畸变非常有利于FM-AFM相变。本研究再现了莫特绝缘Y _1-x La _x TiO的结构，电子和磁性₃，并很好地解释了实验观察到的磁性相变。