Birefringent crystals play a crucial role in the laser polarization of modern laser technologies. As a marvelous branch of optical materials, oxyhalides are attracting extensive interest for their suitable structures and diverse properties. Metal cations with lone pairs have proven advantageous for enhancing birefringence and extending the range of transmission. In this study, we comprehensively investigated the antimony(III) oxyhalide system, Sb–O–X. Specifically, we systematically examined the impact of single-site substitution within a series of compounds, including SbOCl, Sb₂OCl₄, Sb₃O₄F, Sb₃O₄I, Sb₃O₄Cl, Sb₈O₁₁Cl₂, and Sb₈O₁₁Br₂. The substitution of halogens led to significant alterations in the crystal structures, ranging from 0D isolated units to 2D layers, which are favorable for generating birefringences greater than 0.1. These findings underscore the potential of antimony oxyhalides for achieving the balance between birefringence and bandgap, and affirm the viability of single-site substitution as an effective strategy for discovering birefringent materials.

中文翻译：

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通过单中心取代探索锑(III)卤氧化物以寻求大双折射

双折射晶体在现代激光技术的激光偏振中发挥着至关重要的作用。作为光学材料的一个奇妙分支，卤氧化物因其合适的结构和多样化的性能而引起了广泛的兴趣。具有孤对电子的金属阳离子已被证明对于增强双折射和扩大传输范围是有利的。在这项研究中，我们全面研究了锑( III )卤氧化物体系Sb-O-X。具体来说，我们系统地研究了一系列化合物中单点取代的影响，包括SbOCl、Sb ₂ OCl ₄、Sb ₃ O ₄ F、Sb ₃ O ₄ I、Sb ₃ O ₄ Cl、Sb ₈ O ₁₁ Cl ₂，和Sb ₈ O ₁₁ Br ₂。卤素的取代导致晶体结构发生显着变化，从 0D 孤立单元到 2D 层，这有利于产生大于 0.1 的双折射。这些发现强调了卤氧化锑在实现双折射和带隙之间平衡方面的潜力，并肯定了单点取代作为发现双折射材料的有效策略的可行性。