Three pseudo-dimeric lead halide complexes containing derivatives of 8-hydroxyquinoline, Cl2QPbX (X = Br, I), (Cl2Q)4Pb2:Synthesis, crystal structures, and fluorescence spectroscopic properties

Research output: Contribution to journalResearch articleContributedpeer-review


  • Chuan Yu Lan - , Shanghai University of Engineering Science (Author)
  • Yuandong Wu - , Shanghai University of Engineering Science (Author)
  • Dajiang Mei - , Shanghai University of Engineering Science (Author)
  • Shaoguo Wen - , Shanghai University of Engineering Science (Author)
  • Thomas Doert - , Chair of Inorganic Chemistry II, TUD Dresden University of Technology (Author)


Three new complexes, namely (5,7-Dichloro-8-hydroxyquinoline)PbX (X=Br, I) (1, 2) and Pb2(5,7-Dichloro-8-hydroxyquinoline)4 (3), were synthesized through solvent evaporation at ambient temperature. The crystal structures and fluorescence emission properties of these complexes were systematically investigated. An analysis using single crystal X-ray diffraction revealed that complexes 1-3 form pseudo-dimeric structures through the interaction between lead and neighboring oxygen via secondary contacts. A comparison between the structures of complex 2 and [Pb(μ-Q)I]2, a complex of PbI2 with 8-hydroxyquinoline, showed that the coordination polyhedron changed from a triangular pyramid to a distorted tetrahedron. This change may be attributed to the site resistance effect of the chlorine substituents coordinated to the quinoline ring. Complex 3 has a layered structure formed through secondary contacts and intramolecular hydrogen bonding C-H⋯O and C-H⋯Cl among the lamellar molecules. The maximum emission peak at 489 nm, 505 nm, and 543 nm for complex 1-3 can be assigned to the ligand-to-metal charge transfer (LMCT). The maximum emission peaks were red-shifted by 22 nm, 38 nm, and 75 nm, respectively, compared to the ligand. The number of ligands increases the conformational rigidity of the structure and the electron density on lead atoms causing the molecular structure to change, the energy alters, and the fluorescence peaks to move in the long-wave direction.


Original languageEnglish
Article number136685
Journal Journal of molecular structure
Publication statusPublished - 5 Jan 2024

External IDs

ORCID /0000-0001-7523-9313/work/159171522



  • 8-Hydroxyquinoline, Crystal structure, Lead complex, Spectroscopic property