WATER-BRIDGED MOLECULAR ADDUCT OF TETRABROMOCADMATE(II) WITH PROTONATED DAFONE (4,5-DIAZAFLUOREN-9-ONE), (C11H7N2O2[CDBR4].2H(2)O

The structure of the title compound, bis(4H(+)-9-oxo-4,5-diazafluoreni um) tetrabromocadmate(II)-water (1/2), consists of a distorted tetrahe dral (CdBr4)(2-) anion and HL(+) cations, where L is the organic ligan d 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 i n the dafone ring system gives rise to an opening of the C-N-C angle w hen compared with the corresponding value in the neutral form. The dih edral angles between the mean planes of the pyridine rings in each daf one ligand are 2.8 and 3.1 degrees. The water molecules present in the structure are involved in a series of hydrogen-bonding interactions a nd bridge the cadmium tetrabromide and the organic ligand through weak O ... Br interactions.