RbPb8O4Cl9: the first alkali metal lead oxyhalide with distorted [PbO3Cl3] and [PbOCl5] mixed-anion groups. Issue 39 (22nd September 2021) - Fan, Zhongxu
Abstract : The first alkali metal lead oxyhalide RbPb8 O4 Cl9 is designed and synthesized. The compound shows a porous network framework built from unique [PbO3 Cl3 ] and [PbOCl5 ] mixed-anion groups and [RbCl8 ] polyhedra. Abstract : A new heavy metal oxychloride, RbPb8 O4 Cl9, has been synthesized by a high-temperature solution method. The compound crystallizes in the centrosymmetric space group P 4/ n (no. 85) and exhibits a three-dimensional (3D) framework constructed from [PbO3 Cl3 ], [PbOCl5 ] and [RbCl8 ] polyhedra. RbPb8 O4 Cl9 is an indirect band gap compound with an experimental band gap of 3.66 eV. The first-principles calculations indicate that the band gap mainly originated from the interaction of Pb 6p, O 2p and Cl 2p states. Meanwhile, the calculated birefringence of RbPb8 O4 Cl9 is about 0.012 at 1064 nm. The compound is the first alkali metal lead oxyhalide, which enriches the structural diversity of oxyhalides and provides an insight for the exploration of new functional materials.