Molecular and Crystal Structure of 1,10-Phenanthroline Complex with Nitrosonium Cation

1,10-Nitroso-1,10-phenanthrolinium tetrafluoroborate was subjected to X-ray diffraction analysis. A distinctive feature of the complex is the NO group position between two nitrogen atoms of the phenanthroline skeleton, and so the complex may be regarded as belonging to bidentate type. The distance from the N atom of the group to the nitrogens of the skeleton are approximately equal (2.3 Å) and are considerably shorter that the average intermolecular contacts of the pair of nitrogen atoms N...N (3.0 Å). In the crystal two types of cations are present where the NO groups are oriented at angles 54 and 61° with respect to phenanthroline skeleton, and the length of N-O bonds is close to that in NO⁺ cation. The geometrical parameters of cation obtained by ab initio calculations are close to experimental data.