Elektronenspinresonanz‐Untersuchungen von VO2+‐Komplexverbindungen in wässeriger Lösung

The electron paramagnetic resonance and the optical absorption spectra of vanadyl(IV) complexes with a series of organic ligands have been investigated in aqueous solution. The g‐values as well as the nuclear hyperfine splitting constants are found to be sensitive to changes of the ligands. The g‐values indicate that the VO‐«double‐bonding» is maintained in all the compounds examined. The experimental results further suggest that the observed isotropic 51V‐hyperfine structure cannot be accounted for in terms of admixture of excited s‐electrons to be b2‐ground‐state, but rather in terms of «polarization» of filled inner s‐orbitals.