Mixed lone-pair and mixed anion compounds: Pb3(SeO3)(HSeO3)Br3, Pb3(SeO3)(OH)Br3, CdPb8(SeO3)4Cl4Br6 and RbBi(SeO3)F2.

Four new mixed lone-pair mixed anion materials, Pb 3 (SeO 3)(HSeO 3)Br 3 , Pb 3 (SeO 3)(OH)Br 3 , CdPb 8 (SeO 3) 4 Cl 4 Br 6 and RbBi(SeO 3)F 2 , were successfully synthesized by hydrothermal and solid-state techniques. All four compounds exhibit three-dimensional crystal structures, however the frameworks are vastly different. Pb 3 (SeO 3)(HSeO 3)Br 3 exhibits a three-dimensional (3D) structure consisting of sheets of [PbO 5 Br 3 ], [PbO 4 Br 3 ] and [PbO 4 Br 2 ] polyhedra linked to [SeO 3 ] and [SeO 2 (OH)] groups. Pb 3 (SeO 3)(OH)Br 3 also exhibits a 3D framework composed of chains of edge-sharing [PbO 3 (OH)Br 2 ] and [PbO 2 (OH)Br 3 ] octahedra connected by [SeO 3 ] groups. The 3D network of CdPb 8 (SeO 3) 4 Cl 4 Br 6 is composed of 1D [Pb 4 Br 3 Cl 4 ] chains attached to [CdSe 4 O 12 ] units through shared oxygens. Finally, RbBi(SeO 3)F 2 exhibits a 3D network made up of sheets of corner-sharing [BiO 3 F 4 ] and [SeO 3 ] polyhedra. For all of the reported compounds, infrared spectroscopy, UV–vis diffuse reflectance spectroscopy and thermogravimetric measurements were performed. Four new metal-selenium-oxyhalides, Pb 3 (SeO 3)(HSeO 3)Br 3 , Pb 3 (SeO 3)(OH)Br 3 , CdPb 8 (SeO 3) 4 Cl 4 Br 6 and RbBi(SeO 3)F 2 with three-dimensional (3D) structures, have been successfully synthesized and characterized. Image 1 • Four new metal-selenium-oxyhalides, Pb 3 (SeO 3)(HSeO 3)Br 3 , Pb 3 (SeO 3)(OH)Br 3 , CdPb 8 (SeO 3) 4 Cl 4 Br 6 and RbBi(SeO 3)F 2 , were successfully synthesized by hydrothermal and solid-state methods. • All four compounds exhibit three-dimensional crystal structures, however the frameworks are vastly different. • Infrared spectroscopy, UV–vis diffuse reflectance spectroscopy and thermogravimetric measurements were performed for all of the reported compounds. [ABSTRACT FROM AUTHOR]