Zero-Dimensional Oxyselenide Ba<sub>12</sub>[(Ga<sub>2</sub>OSe<sub>5</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)]: Enhanced Optical Anisotropy through Heteroanionic Engineering
The rational design of chalcogenides with exceptional optical properties remains a significant challenge. Here, we employ heteroanionic engineering to incorporate selenium into the celsian-type BaGa<sub>2</sub>Si<sub>2</sub>O<sub>8</sub>, synthesizing a novel zero-dimensional oxyselenide, Ba<sub>12</sub>[(Ga<sub>2</sub>OSe<sub>5</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)]. It crystallizes in the hexagonal space group <i>P</i>6<sub>3</sub>/<i>m</i> and features isolated [Si<sub>2</sub>O<sub>7</sub>] and [Ga<sub>2</sub>OSe<sub>5</sub>] clusters, balanced by Ba<sup>2+</sup> cations. The [Ga<sub>2</sub>OSe<sub>5</sub>] unit, reported for the first time in oxychalcogenides, marks a structural breakthrough. The compound exhibits a wide bandgap (E<sub>g</sub> = 3.14 eV), broad IR transmission (0.39-20.4 μm), and high thermal stability (up to 1100 K). Theoretical calculations reveal that the compound exhibits a 18-fold enhancement in birefringence, increasing from 0.0038 to 0.068 at 1064 nm, compared to its parent structure. This significant improvement is largely due to the role of the [Ga<sub>2</sub>OSe<sub>5</sub>] unit in enhancing optical anisotropy. This work highlights the potential of heteroanionic engineering for designing advanced birefringent materials, paving the way for functional optical crystals.
Authors
- Qi‐Long Zhu (ORCID: https://orcid.org/0000-0001-9956-8517)
- Hua Lin (ORCID: https://orcid.org/0000-0002-7241-9623)
- Bo Zhang (ORCID: https://orcid.org/0000-0001-7355-0941)
- Shenghua Zhou (ORCID: https://orcid.org/0000-0003-3871-9099)
- Xin‐Tao Wu
- Yong‐Fang Shi
Institutions
- Chinese Academy of Sciences (CN)
- Fujian Institute of Research on the Structure of Matter (CN)
- Jiangsu University of Technology (CN)
- Clean Energy (United States) (US)
- Tan Kah Kee Innovation Laboratory (CN)
- University of Chinese Academy of Sciences (CN)
- State Key Laboratory of Structural Chemistry
Publication Details
- Journal
- Inorganic Chemistry
- Published
- 2025-04-11
- DOI
- https://doi.org/10.1021/acs.inorgchem.5c01251
- Citations
- 3
- Primary Topic
- Crystal Structures and Properties
- Type
- article
- Field-Weighted Citation Impact
- 1.28
Funders
- National Natural Science Foundation of China
- Natural Science Foundation of Fujian Province