Birefringent compounds play an indispensable role in modern optoelectronics and information communication. In this article, the electronic structures and birefringence of binary and ternary antimony halides are investigated using the first-principles method. The results show that the stereochemical activity of antimony cations in these compounds gradually decreases from Cl to I, and the birefringence of these compounds gradually increases from Cl to I. The degree of stereochemical activity of lone pairs is determined by the energy difference between the s-state of the cation and the p-state of the halogen, implying the revised model about stereochemical activity of lone-pairs in metal oxides is also appropriate for metal halides. The real-space atomic cutting and Born effective charges show that the antimony cations and halogen closer to Fermi level give main contribution to birefringence. And the occupied p-states of antimony and halogen atoms play an important role in determining the birefringence.

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卤化锑不同序列立体化学活性和双折射的第一性原理研究

双折射化合物在现代光电子学和信息通信中发挥着不可或缺的作用。在本文中，使用第一性原理方法研究了二元和三元卤化锑的电子结构和双折射。结果表明，这些化合物中锑阳离子的立体化学活性从Cl到I逐渐降低，这些化合物的双折射从Cl到I逐渐增加。孤对的立体化学活性程度取决于s之间的能量差。阳离子的 - 态和卤素的 p 态，暗示关于金属氧化物中孤对立体化学活性的修正模型也适用于金属卤化物。实空间原子切割和玻恩有效电荷表明，更接近费米能级的锑阳离子和卤素对双折射的贡献主要。锑和卤素原子的占据 p 态在确定双折射中起重要作用。