title: Be2BO3F: A Phase of Beryllium Fluoride Borate Derived from KBe2BO3F2 with Short UV Absorption Edge.
abstract: A phase of beryllium fluoride borate Be2BO3F (BBF) was successfully developed and grown by spontaneous nucleation from high temperature solution. The crystal belongs to the trigonal space group of R3̅c (No. 167), with lattice parameters a = 4.442(1) Å, c = 24.956(5) Å, and Z = 2. It is constructed by the infinite planar [Be2BO3F2]∞ layers, in which the planar triangle [BO3](3-) and the tetrahedral [BeO3F](5-) anionic groups are arranged in parallel via corner-sharing O atoms in each ab plane. BBF is an incongruent compound and decomposes at about 650 °C. The deep-ultraviolet (DUV) transmittance spectrum reveals that its UV cutoff wavelength is down to ∼150 nm. Theoretical calculations show that BBF has a large birefringence (Δn = 0.13 at 200 nm), which mainly originates from the infinite planar [Be2BO3F2]∞ layers. In conclusion, BBF may be served as a potential DUV birefringent material.
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Shu
authors.initials: S
authors.lastname: Guo
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Liu
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Mingjun
authors.initials: M
authors.lastname: Xia
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Kang
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Li
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Wang
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Zheshuai
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Chuangtian
authors.initials: C
authors.lastname: Chen