Inorganic Chemistry, Vol.34, No.1, 193-198, 1995
Electronic and Structural Investigations of Technetium Compounds by X-Ray-Absorption Spectroscopy
X-ray absorption near edge structure spectroscopy has been used to establish the chemical shifts of the technetium K edge ina range of compounds containing Tc in a variety of formal oxidation states. The edge positions span 19.9 eV from Tc metal to NH4TcO4. Strong correlation between chemical shift and formal oxidation state is observed. Extended X-ray absorption fine structure (EXAFS) spectroscopy of Tc-2(CO)(10) indicates that multiple scattering along the Tc-C-vector is more important than direct Tc..O scattering. TcO2 is shown by EXAFS to possess a distorted rutile structure with a closest Tc-Tc distance of 2.61 Angstrom. This is rationalized in terms of the Goodenough model for bonding in transition metal dioxides.