Water-Bridged Molecular Adduct of Tetrabromocadmate(II) with Protonated Dafone (4,5-Diazafluoren-9-one), (C11H7N2O)2[CdBr4].2H2O

The structure of the title compound, bis(4H + -9-oxo-4,5-diazafluorenium) tetrabromocadmate(II)-water (1/2), consists of a distorted tetrahedral (CdBr 4 ) 2- anion and HL + cations, where L is the organic ligand dafone (4,5-diazafluoren-9-one). There is no direct bonding between the metal atom and the ligand. The protonation of one of the N atoms in the dafone ring system gives rise to an opening of the C-N-C angle when compared with the corresponding value in the neutral form. The dihedral angles between the mean planes of the pyridine rings in each dafone ligand are 2.8 and 3.1°. The water molecules present in the structure are involved in a series of hydrogen-bonding interactions and bridge the cadmium tetrabromide and the organic ligand through weak O...Br interactions.