Structure, growth and properties of a novel polar material, KSr4B3O9

A novel polar material, KSr4B3O9, has been obtained by the high temperature solution method for the first time. It crystallizes in the polar space group Ama2. The material exhibits a three-dimensional structure consisting of interconnecting KO10 groups, SrOx (x=8, 9) units and isolated BO3 triangles. DSC/TG curve shows that KSr4B3O9 melts incongruently. The calculated band structures and the density of states of KSr4B3O9 suggest that its direct gap is 3.897 eV. The absorption spectrum indicates the absorption edge of KSr4B3O9 is about 302 nm. It produces SHG intensity about as large as that of KH2PO4 (KDP) and is phase matchable.

Viewed along the c-axis, B(2)O3 triangles and B(3)O3 triangles are parallel with the (0 1 0) face and opposite to each other. However, all the B(1)O3 triangles have the same direction along the c-axis. So the main SHG efficiency of the compound comes from B(1)O3 triangles according to the anion group theory.Figure optionsDownload as PowerPoint slideHighlights
► A polar material, KSr4B3O9, has been obtained by high temperature solution method.
► The material consists of KO10 units, SrOx(x=8, 9) units and isolated BO3 units.
► KSr4B3O9 produces SHG intensity as large as that of KDP and is phase matchable.
► The absorption edge of KSr4B3O9 is about 302 nm.