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Updated: Oct 4, 2025

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
K3V2O3F4(IO3)3: a high-performance SHG crystal containing both five and six-coordinated V5+ cations
Jin Chen1,2,3, Chun-Li Hu1, Yi-Lin Lin1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou 350002 P. R. China mjg@fjirsm.ac.cn.
Abstract:
The combination of d0 transition metal oxofluorides with iodate anions helps to synthesize polar crystals. Herein, a novel polar crystal, K3V2O3F4(IO3)3, which is the first metal vanadium iodate with two types of V5+-centered polyhedra (VO4F2 octahedron and VO3F2 trigonal bipyramid), has been prepared hydrothermally. It crystallizes in the polar space group of Cmc21 and its structure displays an unprecedented 0D [V2O3F4(IO3)3]3- anion, which is composed of Λ-shaped cis-[VO2F2(IO3)2]3- and [VO2F2(IO3)]2- anions interconnected via the corner-sharing of one oxo anion. The synergy gained from the VO4F2, VO3F2 and IO3 groups resulted in K3V2O3F4(IO3)3 exhibiting both a strong second-harmonic generation (SHG) response (1.3 × KTiOPO4) under 2050 nm laser irradiation and a large birefringence (0.158 @ 2050 nm). This study provides a facile route for designing SHG materials by assembling various vanadium oxide-fluoride motifs and iodate anions into one compound.
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