Low temperature synthesis and characterization of SnTa2O6

Abstract Sn(II)Ta 2 O 6 is well known as the mineral Thoreaulite, but attempts to prepare it by direct combination of SnO and Ta 2 O 5 fail. SnTa 2 O 6 has now been synthesized by reacting SnCl 2 with KTaO 3 at 673 K under an inert atmosphere. Although a reported structure determination of SnTa 2 O 6 indicated an acentric space group, our second harmonic generation (SHG) studies indicate that SnTa 2 O 6 is centrosymmetric as is the case for isostructural SnNb 2 O 6 .