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Updated: Aug 5, 2026
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Local Structure and Electronic State of Technetium in Pentacarbonyl Hydride TcH(CO)5
Anna D Krot1, Daniil A Novichkov1, Anna P Sakhonenkova2,3
1Department of Chemistry, Lomonosov Moscow State University, Leninskiye Gory, 1 build. 3119991Moscow, Russia.
Abstract:
Technetium pentacarbonyl hydride 99TcH(CO)5 was studied using X-ray absorption spectroscopy at the Tc K-edge, complemented by a series of 99TcX(CO)5 (X = Cl, Br, I, 99Tc(CO)5) as the references. Experimental Tc K-edge XANES and EXAFS data were interpreted with the aid of density functional theory and advanced spectral modeling. EXAFS analysis of liquid pentacarbonyl hydride showed that the Tc-C and Tc-O interatomic distances in the molecule of this complex were close to those in 99Tc2(CO)10. The Tc K-edge XANES fingerprint and the first-shell EXAFS responses are largely controlled by the carbonyl coordination, whereas the nature of the X ligands in a series of 99TcX(CO)5 (X = Cl, Br, I, 99Tc(CO)5) exerts only a secondary role. The combined experimental and computational results further elucidate the factors underlying the enhanced stability of 99TcH(CO)5 toward carbonyl substitution.
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