Strong Second Harmonic Generation (SHG) Originating from Combined Second-Order Jahn鈥揟eller (SOJT) Distortive Cations in a New Noncentrosymmetric Tellurite, InNb(TeO4)2
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- 作者：Yeong Hun Kim ; Dong Woo Lee ; Kang Min Ok
- 刊名：Inorganic Chemistry
- 出版年：2014
- 出版时间：May 19, 2014
- 年：2014
- 卷：53
- 期：10
- 页码：5240-5245
- 全文大小：385K
- 年卷期：v.53,no.10(May 19, 2014)
- ISSN：1520-510X
文摘
Pure polycrystalline bulk samples and single crystals of a novel polar noncentrosymmetric (NCS) indium niobium tellurium oxide, InNb(TeO4)2, have been synthesized through solid-state reactions with In2O3, Nb2O5, and TeO2. InNb(TeO4)2 exhibits a three-dimensional structural backbone consisting of layers of corner-shared InO6 octahedra, layers of corner-shared NbO6 octahedra, and chains of corner-shared TeO4 polyhedra. The infrared spectrum shows In鈥揙, Nb鈥揙, and Te鈥揙 vibrations, and the UV鈥搗is diffuse reflectance spectrum shows a band gap of 3.5 eV for the reported material. Thermal analysis indicates that InNb(TeO4)2 is thermally stable to 740 掳C. Powder second-order nonlinear optical (NLO) measurements reveal that InNb(TeO4)2 has a strong second harmonic generation (SHG) efficiency, 100 times that of 伪-SiO2. A detailed structural examination indicates that the strong SHG is due to the combined net polarization originating from the distorted environment of second-order Jahn鈥揟eller (SOJT) cations such as Nb5+ and Te4+. Elemental analysis, the magnitude of distortion, and calculations of dipole moments for InNb(TeO4)2 are also presented.