Na2Mg1−xZnxSiO4 (0 ≤ x ≤ 1): Noncentrosymmetric Sodium Metal Silicate Solid Solutions with Ultraviolet Nonlinear Optical Properties

摘要

Stoichiometrically equivalent noncentrosymmetric (NCS) sodium metal silicates, Na2MgSiO4 and Na2ZnSiO4, and their solid solutions have been synthesized via solid‐state reactions. The structures of the reported materials were determined by powder X‐ray diffraction using the Rietveld method. A careful structural analysis indicates that the unit cell volumes of Na2Mg1?xZn xSiO4 solid solutions decrease as more Zn2+ cations are doped into the site of Mg2+. Also, the synthesized silicate solid solutions revealed three‐dimensional frameworks consisting of highly distorted yet well‐aligned MgO4 (or ZnO4) and SiO4 tetrahedra. The title compounds exhibit very large band gaps ranging from 5.57 to 6.05?eV. Second‐harmonic generation (SHG) measurements indicate that the solid solutions are phase‐matchable and the SHG efficiencies increase as more d10 cation, Zn2+, is added to the backbone. A complete characterization is presented along with the explanation of the structure‐SHG property relationship.