The frequency conversion effect of ultraviolet (UV) and deep ultraviolet (DUV, λ<200 nm) nonlinear optical crystals is one of the most effective solutions to achieve UV/DUV all-solid coherent light. The design and preparation of practical UV/DUV nonlinear optical crystals have always been the focus of research in the field of photoelectric functional crystals. The Research Center for Crystal Materials of Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (XTIPC, CAS) has been committed to the research of novel nonlinear optical crystals for a long time and has made a series of important progress.

In the past decades, aluminoborate has developed rapidly due to its low toxicity, stable physical and chemical properties, and easy crystal growth. A series of excellent short-wavelength nonlinear optical crystals have been discovered successively. From the perspective of structural design, when Al [Ne]3s²3p¹ atom with empty d orbital bonds with O/F atom, the [AlO_mF_n] (m + n = 4, 5, 6) groups can be formed by sp³, sp³d, and sp³d² hybrid orbitals. The rich variety of Al-O/F groups can further regulate the structure and properties. Recently, the research team led by Prof. Shlie Pan and Prof. Min Zhang from XTIPC, CAS systematically investigated the progress of aluminoborate from traditional aluminoborate to aluminoborate fluoride and fluoroaluminoborate, focusing on its structure-property relationship and potential application as UV/DUV nonlinear optical crystal materials. Some constructive ideas are put forward to guide the design of high-performance nonlinear optical crystal materials in the future. The research result titled "Aluminoborates as Nonlinear Optical Materials" was published in Angewandte Chemie International Edition. Prof. Shilie Pan and Prof. Min Zhang from XTIPC, CAS were the corresponding authors, and Jiahao Jiao, a doctoral student from Research Center for Crystal Materials, XTIPC, CAS was the first author. This research was supported by the Youth Promotion Association of the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the Major Projects of the Autonomous Region.

Article link: https://doi.org/10.1002/anie.202217037