Ba4Ag5(IO3)6(I3O8)3(I4O11)2: a nonlinear optical crystal containing two types of polyiodate anions

Abstract

Herein, a novel metal polyiodate, namely, Ba₄Ag₅(IO₃)₆(I₃O₈)₃(I₄O₁₁)₂, has been prepared by using H₃PO₄ (≥85 wt% in H₂O) as the reaction medium. Ba₄Ag₅(IO₃)₆(I₃O₈)₃(I₄O₁₁)₂ is the first metal iodate containing different polyiodate groups [(I₃O₈)⁻ trimer and (I₄O₁₁)²⁻ tetramer]. Ba₄Ag₅(IO₃)₆(I₃O₈)₃(I₄O₁₁)₂ crystallizes in the noncentrosymmetric space group of Pnc2, and its crystal structure exhibits a 3D network based on two different anionic frameworks, 2D [Ag₅(I₃O₈)₃(IO₃)₄]²⁻ and 3D [Ba₄(IO₃)₆(I₃O₈)₃(I₄O₁₁)₂]⁵⁻, via the connection of (IO₃)⁻ and (I₃O₈)⁻ anions. Importantly, Ba₄Ag₅(IO₃)₆(I₃O₈)₃(I₄O₁₁)₂ shows a moderate second-harmonic generation effect (2.5 × KH₂PO₄) under 1064 nm laser radiation, suitable birefringence (0.082@1064 nm) for achieving phase matching and a high power laser-induced damage threshold (85.67 MW cm⁻²@1064 nm, 10 ns).