Ba3Zn4Si4O15: A Novel Centrosymmetric Silicate with Isolated SiO4 and Si2O7 Units

A new silicate Ba3Zn4Si4O15 (BZSO), was synthesized by the high‐temperature solution method in the open air, and the structure was determined using single‐crystal X‐ray diffraction data. The compound can be regarded as a derivative of α‐SiO2 tetrahedral framework. The structural analysis indicates that it crystallizes in the centrosymmetric space group C2/c (No. 15) with lattice parameters a = 19.3931(12) Å, b = 5.1262(4) Å, c = 16.3620(12) Å, β = 115.7 °, V = 1465.5 Å3, Z = 4 of a monoclinic crystal system composed of isolated Si2O7 dimers, and SiO4, ZnO4 tetrahedra. Experimental characterization demonstrates that it possesses birefringence of 0.013@546.1 nm. Besides, the first‐principles theoretical calculations were carried out to elucidate the relationship between the electronic structure and optical property.