A new tantalate compound KSr 2Ta 3O 10 was synthesized by solid state reaction for the first time in the ternary system K 2O SrO Ta 2O 5, and its single crystals were prepared using flux method. The chemical compositions, crystal structure, optical property, density and melting point of the new compound were characterized by EPMA, XRD, DTA and so on. KSr 2Ta 3O 10 crystallizes the orthorhombic system with unit cell parameters a= 0.784 4(1) nm, b =0.777 0(1) nm, c =3.012 7(1) nm and space group P 2 12 12 1, Z =8. The structure may be described as treble perovskite sheets [Sr 2Ta 3O 10 ] - interleaved with K +. Further, it was found that KSr 2Ta 3O 10 has intercalation phenomenon. Na +, Li +, H +, NH + 4 could exchange the interlayer cations K + of KSr 2Ta 3O 10 , and n hexylamine also could intercalate into the place between the layers of [Sr 2Ta 3O 10 ] -. [WT5HZ]
