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Updated: Aug 20, 2025
Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area
Published on: February 19, 2018
Growth, Structure, and Optical Properties of a Nonlinear Optical Niobium Borate Crystal CsNbOB2O5 with Distorted NbO5
Juhe Liu1,2,3, Ming-Hsien Lee4, Chunxiao Li1,2,3
1Beijing Center for Crystal Research and Development, Key Lab of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Abstract:
In this paper, a revised structure determination of an already known compound CsNbOB2O5 with new structural insights was performed and the detailed characterization of its optical properties was reported for the first time. CsNbOB2O5 was synthesized by spontaneous crystallization. It crystallizes in the Pmn21 space group, and the unit lattice parameters are a = 7.5220(7) Å, b = 3.9881(4) Å, c = 9.7167(9) Å, and Z = 2. In the structure of CsNbOB2O5, a [NbO5] square pyramid and [B2O5] unit are linked to constitute an infinitely extended two-dimensional ∞2[NbOB2O5] layer via sharing oxygen atoms. Between these two-dimensional layers, there are no covalent bonds perpendicular to their planes based on Mulliken bond order analysis. CsNbOB2O5 has a wide band gap (4.52 eV) and a large second-harmonic-generation (SHG) response (1.2 × KDP) and demonstrates type-I phase-matchable behavior. First-principles simulations reveal that the birefringence is approximately 0.10. Moreover, SHG-weighted charge density analysis shows that the primary source of the nonlinearity of the title compound is the distorted NbO5 square pyramids.
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