organic compounds
Open access
The crystal structure of the title compound, C19H15O2P, features pairs of molecules joined by O—HO hydrogen bonds across crystallographic inversion centers. In addition, π–π interactions, with a centroid–centroid distance of 3.6273 (9) Å between the fluorene ring systems, connect the dimers into chains along [01-1]. The three rings make dihedral angles of 1.34 (9), 1.52 (10) and 1.51 (7)° with each other.
metal-organic compounds
Open access
The structure of the title compound, [Co(NO2)2(NH2CH2CH2NH2)2][Co(NO2)4(NH2CH2CH2NH2)]·H2O, was redetermined with a modern CCD-equipped diffractometer. In comparison with the original determination based on photographic data [Kushi et al. (1976). Inorg. Nucl. Chem. Lett. 12, 629–633], the current study allows the location of reliable postions for the H atoms and thus leads to better understanding of the interionic and intermolecular interactions. The crystal structure consists of an octahedrally coordinated cationic CoIII complex ion, an octahedrally coordinated anionic CoIII complex ion and a lattice water molecule. The complex cation, complex anion and lattice water molecule are connected by an intricate network of O—HO and N—HO hydrogen bonds, forming a three-dimensional structure.