Explorations of new second-order NLO materials in the Ag-I-Mo-VI/W-VI-Te-IV-O systems

Explorations of new second-order NLO materials in the Ag-I-Mo-VI/W-VI-Te-IV-O systems led to three new mixed metal tellurites, namely, Ag2Mo3Te3O16, Ag2MoTe4O12 and Ag6W3Te4O20. Ag2Mo3Te3O16 is isostructural with Na2Mo3Te3O16 and its structure features one-dimensional [Mo3Te3O16](2-) anionic chains composed of [Mo3O14](10-) clusters interconnected by [Te3O8](4-) anions via corner-sharing, such 1D chains are further interconnected by Ag+ ions into a 3D network. Ag2MoTe4O12 is isostructural with Na2MoTe4O12 and its structure features 3D anionic [MoTe4O12](2-) network with the Ag+ ions filling the cavities of the structure. Ag6W3Te4O20 belongs to a new structural type. Its structure composed of 1D [WO2(TeO3)(2)](2-) anionic chains and 2D[W2O6(TeO3)(2)](2-) anionic layers, the above two types of anionic building units are interconnected by Ag+ ions into a 3D condensed network. Second harmonic generation (SHG) measurements indicate that Ag2Mo3Te3O16 displays a very large SHG response of approximately x 8 KDP. Band structure calculations based on DFT methods for all three compounds have also been performed.