Tl(VO)2O2(IO3)3: a new polar material with a strong SHG response.

The synthesis, crystal and band structures and optical characterizations of a new polar thallium(I) vanadyl iodate, namely Tl(VO)2O2(IO3)3, are reported. Tl(VO)2O2(IO3)3 crystallizes in the orthorhombic polar space group Ima2 (No. 46) with a = 14.1143(17), b = 10.2116(12), c = 8.0319(9) Å, V = 1157.6(2) Å(3) and Z = 4. The structure of Tl(VO)2O2(IO3)3 exhibits a 1D [(VO)2O2(IO3)3](-) chain in which neighboring distorted VO6 octahedra are interconnected by both bridging oxo and iodate anions. The SHG measurements on Tl(VO)2O2(IO3)3, using a 2050 nm laser radiation, showed a moderate strong SHG response of 1.2 × KTP(KTiOPO4). Furthermore, the material is phase-matchable. Theoretical calculations based on DFT methods were performed by using the total-energy code CASTEP.