2025-11-14 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research_news/chem/202511/t20251114_1115615.shtml
- https://pubs.acs.org/doi/10.1021/acs.chemmater.5c02373
希土類金属中心多面体によるアルカリ金属硫酸塩の複屈折の増強と陽イオンによる構造制御 Enhancement of Birefringence in Alkali Metal Sulfates Induced by Rare Earth Metal-Centered Polyhedra and Structure Regulation via Cations
Luyong Zhang,Zhencheng Wu,Jingdong Yan,Shibin Wang,Zilong Chen,Zhihua Yang,Fangfang Zhang,and Shilie Pan
Chemistry of Materials Published October 23, 2025
DOI:https://doi.org/10.1021/acs.chemmater.5c02373
Abstract
Sulfates have remained promising candidates for deep-ultraviolet (DUV) optical crystals owing to the inherently wide bandgaps induced by the [SO4] tetrahedral groups. However, the structural rigidity of [SO4] tetrahedra imposes severe restrictions on the polarization anisotropy, fundamentally preventing sulfates from achieving sufficient birefringence required for regulating light polarization. Herein, by incorporating f0 rare earth metal cation Y3+ into alkali metal sulfates, we synthesized six compounds, AY(SO4)2 and A3Y(SO4)3 (A = K, Rb, Cs). They exhibit dramatically enhanced birefringence between 0.013–0.056 at 546 nm, with up to 25 times that of their parent alkali metal sulfates, which originate from the highly aberrant Y–O polyhedra and the dimensionality reduction of the Y–O–S network regulated by A-site cations. This study provides valuable insights into the further exploration of sulfate-based optical materials.
