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, Ag(2)Mo(3)Te(3)O(16), Ag(2)MoTe(4)O(12) and Ag(6)W(3)Te(4)O(20). Ag(2)Mo(3)Te(3)O(16) is isostructural with Na(2)Mo(3)Te(3)O(16) and its structure features one-dimensional Mo(3)Te(3)O(16) anionic chains composed of Mo(3)O(14) clusters interconnected by Te(3)O(8) anions via corner-sharing, such 1D chains are further interconnected by Ag(+) ions into a 3D network. Ag(2)MoTe(4)O(12) is isostructural with Na(2)MoTe(4)O(12) and its structure features 3D anionic MoTe(4)O(12) network with the Ag(+) ions filling the cavities of the structure. Ag(6)W(3)Te(4)O(20) belongs to a new structural type. Its structure composed of 1D WO(2)(TeO(3))(2) anionic chains and 2D W(2)O(6)(TeO(3))(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 Ag(2)Mo(3)Te(3)O(16) 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.