P. Zhao, M. Murshed, E. Alekseev
Dec 1, 2014
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Influential Citations
10
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Journal
Materials Research Bulletin
Abstract
Abstract Single crystal and polycrystalline powder samples of sodium arseno-tungstate of composition Na[AsW 2 O 9 ] were synthesized using high-temperature solid-state methods. The greenish single crystals of the phase were characterized by X-ray diffraction data structure determination and the bulk compound confirmed by powder X-ray data Rietveld refinements. Additionally, scanning electron microscopy (SEM) attached with energy dispersive X-Ray spectroscopy (EDX), thermogravimetry (TG), differential scanning calorimetry (DSC), fourier transform infrared (FTIR) and Raman spectroscopy was performed. A comparative study between Na[AsW 2 O 9 ] and isotypic K[AsW 2 O 9 ] demonstrates the structural modifications and the consequent properties. Placing sodium in the channel of the arseno-tungstate framework, the average As O and W O bond distances did not change due to their rigid-unit like behaviors. However, the unit cell volume contracted about 7.4% caused by shrinkage of the channel dimensions due to shorter Na O bond distances. The non-linear optical property of the compound has been explained in terms of asymmetric W O and As O chemical bonding led by WO 6 and AsO 4 polyhedral distortion, respectively.