Zhang Ming-Zhi, Zhao Yue, Hu Chun-Li, Mao Jiang-Gao
State Key Laboratory of Functional Crystals and Devices, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou 350002 P. R. China
University of Chinese Academy of Sciences Beijing 100049 P. R. China.
Chem Sci. 2025 Jun 4. doi: 10.1039/d5sc01983d.
Exploring infrared (IR) birefringent materials with both large birefringence (Δ) and wide band gaps ( ) is urgently demanded for high-power optoelectronic applications and has long been a tough challenge due to the intrinsic contradictory relationship between the two metrics. Herein, we developed a target-driven closed-loop framework in coupling with functional motif and crystal structure screening, deep learning assisted high-throughput optical property computation, targeted experiment and mechanism investigation, enabling efficient discovery of potential birefringent materials. Utilizing it, a batch of superior IR birefringent crystals containing planar [BS] and/or stereochemically active lone pair (SCALP) groups ([SbS], [SnS], ) were identified: six with huge birefringence (Δ > 1.0) and three with both large birefringence (Δ > 0.5) and wide band gaps ( > 3.5 eV). Remarkably, benefiting from a maximal synergy of [BS] and [SbS] motifs achieved by an optimal assembly of 1D [SbBS] chains, BaSbBS was highlighted and then validated experimentally as the most promising IR birefringent crystal, unlocking a record high birefringence in the wide-band-gap range (Δ = 0.95 & 2.70 eV). This work not only discovers new high-performance birefringent crystals but also offers a universal avenue for precise and efficient evaluation of optical functional materials.
对于高功率光电子应用而言，迫切需要探索同时具有大双折射（Δ）和宽带隙（ ）的红外（IR）双折射材料。由于这两个指标之间存在内在的矛盾关系，长期以来这一直是一项艰巨的挑战。在此，我们开发了一种目标驱动的闭环框架，结合功能基序和晶体结构筛选、深度学习辅助的高通量光学性质计算、有针对性的实验和机理研究，能够高效发现潜在的双折射材料。利用该框架，我们鉴定出了一批含有平面[BS]和/或立体化学活性孤对（SCALP）基团（[SbS]、[SnS]、 ）的优质IR双折射晶体：六种具有巨大双折射（Δ>1.0），三种同时具有大双折射（Δ>0.5）和宽带隙（ >3.5 eV）。值得注意的是，得益于通过一维[SbBS]链的最佳组装实现的[BS]和[SbS]基序的最大协同作用，BaSbBS脱颖而出，并通过实验验证为最有前途的IR双折射晶体，在宽带隙范围内解锁了创纪录的高双折射（Δ = 0.95 & 2.70 eV）。这项工作不仅发现了新的高性能双折射晶体，还为光学功能材料的精确高效评估提供了一条通用途径。
