Syntheses, Crystal Structures, and Optical Properties of Indium Arsenic(III) Oxide Halides: In₂(As₂O₅)Cl₂ and In₄(As₂O₅)(As₃O₇)Br₃

Abstract

Abstract Two new indium arsenic(III) oxide halides, In 2 (As 2 O 5 )Cl 2 ( 1 ) and In 4 (As 2 O 5 )(As 3 O 7 )Br 3 ( 2 ), have been prepared by solid‐state reaction. Both of the compounds feature layered structures, in which indium–oxide halide octahedral rings or indium–oxo chains are bridged by indium–oxide halide octahedral dimers or indium–oxo unicapped trigonal prisms, and the interlinkage between the rings or chains is also consolidated by (As 2 O 5 ) 4– anions for 1 , or (As 2 O 5 ) 4– and (As 3 O 7 ) 5– anions for 2 . Compound 2 is the first compound in which three different indium‐ion coordination geometries coexist with the In 3+ cations coordinated by O 2– and Br – to form [InO 6 ], [InO 7 ], and [InOBr 3 ] units. The diffuse reflectance spectra and band‐structure calculations show that they are wide‐band‐gap semiconductors.