Crystal structure of bis-[octa-kis-(di-methyl sulfoxide-κ O )-ytterbium(III)] penta-bromido-plumbate(II) tribromide di-methyl sulfoxide monosolvate: a ytterbium-doped lead halide perovskite precursor.

A mixture of PbBr 2 and YbBr 3 · n H 2 O in a dimethyl sulfoxide (DMSO) solution yielded single crystals of a lead halide perovskite precursor with ytterbium, bis-[octa-kis-(di-methyl sulfoxide)-ytterbium(III)]penta-bromido-plumbate(II) tri-bromide with di-methyl sulfoxide as co-crystallite, [Yb(C 2 H 6 OS) 8 ][PbBr 5 ] 0.5 Br 1.5 ·0.5C 2 H 6 OS. The complex ions PbBr 5 3- and Yb(DMSO) 8 3+ are present in the crystal together with three Br - ions and DMSO mol-ecules. X-ray crystallography revealed that the Br - ions in YbBr 3 are replaced by the solvent and bound to a Pb II atom or remain free. The presence of PbBr 5 3- units, which are mol-ecular ions with a square-pyramidal structure, is also observed. These single crystals react with a caesium chloride solution, exhibiting near-infrared (NIR) luminescence by visible photoexcitation, suggesting the formation of Yb 3+ -doped lead halide perovskites (CsPbBr 3- x Cl x ·Yb 3+ ).