New NMR investigation of [RuF^sub 5^NO]^sub 2^- anion

The 15N shift value is the main distinctive parameter to distinguish linear than angular MNO in transition metal nitrosyls by NMR spectroscopy. To get insight into the spectroscopic properties of a simple ruthenium-nitrosyl complex, the [RuF5NO]2− anion, was reinvestigated. Their 15N and 19F nuclear magnetic resonance spectra (NMR) were analyzed and compared with the behavior observed for the geometrically related (C4v) [Fe(CN)5NO]2− (15N and 13C enriched) ion. The different splitting and coupling constants observed in both systems were attributed to the small change in angles and atomic distances. These results highlight the sensitivity of this spectroscopy to detect small geometrical distortion in transition metal complexes. DFT calculations predicted for both systems, shifts and coupling constant values in good agreement with the experimental results. The chemical shifts and coupling constants parameters predicted by DFT calculations for both systems are in good agreement with experimental values.