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Updated: Jun 1, 2026
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Electronic and molecular structures of trans-dioxotechnetium(V) polypyridyl complexes in the solid state
Sayandev Chatterjee1, Andrew S Del Negro, Zheming Wang
1Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Novel technetium(V) dioxo complexes exhibit luminescence, allowing direct comparison with rhenium analogs. These findings offer insights into the fundamental properties of d(2) metal-oxo compounds.
Area of Science:
- Inorganic Chemistry
- Coordination Chemistry
- Photophysics
Background:
- Technetium(V) complexes are of interest due to their potential applications and unique electronic structures.
- Understanding the luminescence properties of technetium complexes is crucial for developing new materials and probes.
- Previous studies have focused on rhenium analogs, creating a need for direct comparison with technetium.
Purpose of the Study:
- To synthesize and characterize novel trans-dioxotechnetium(V) complexes.
- To investigate the luminescence properties of these technetium complexes using spectroscopic methods.
- To compare the luminescence behavior of technetium(V) complexes with their rhenium(V) analogs.
Main Methods:
- X-ray crystallography for structure determination.
- Emission spectroscopy at variable temperatures (room temperature down to 8 K).
- Time-dependent theoretical calculations for excited-state distortions.
Main Results:
- The structures of three novel trans-dioxotechnetium(V) complexes were determined.
- Complexes exhibited broad, structureless luminescence at room temperature, with emission maxima around 710-750 nm.
- Cooling to 8 K revealed distinct vibronic features in the emission spectra, characteristic of O═Tc═O and Tc-L stretching modes.
- Theoretical calculations supported the experimental findings regarding excited-state distortions.
Conclusions:
- The study reports the first direct comparison of luminescence properties between second-row (Tc) and third-row (Re) d(2) metal-oxo congeners.
- The luminescence originates from a triplet excited state, similar to rhenium analogs.
- The findings provide a foundation for understanding and manipulating the photophysical properties of technetium complexes.
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