3.2 Alkaline solutions
63
Table 3.8 Standard reduction potential of selected technetium red–ox couples (values with
uncertainties given are recommended in Rard et al. 1999 and later updates)
Oxidation states of Tc Redox reaction
E ⦵ /V
VII/VI
TcO
−
4 + e − TcO
2−
4
−0.64 ± 0.03
VII/V
TcO
−
4 + 2e − TcO
3−
4
−0.60 ± 0.05
VII/IV
TcO
−
4 + 4H + + 3e − TcO 2 · xH 2 O(s) + (2 − x)H 2 O 0.746 ± 0.012
2TcO
−
4 + 10H + + 6e − Tc 2 O 2 (OH)
2+
2 + 4H 2 O
0.731 ± 0.011
TcO
−
4 + 6H + + 3e − TcO 2+ + 3H 2 O
0.660
TcO
−
4 + 4H + + 3e − TcO(OH) 2 (aq) + H 2 O
0.595 ± 0.046
VII/III
TcO
−
4 + 8H + + 4e − Tc 3+ + 4H 2 O
0.576
VII/0
TcO
−
4 + 8H + + 7e − Tc + 4H 2 O
0.472
IV/III
TcO(OH) 2 (aq) + 4H + + e − Tc 3+ + 3H 2 O
0.516
Tc 2 O 2 (OH)
2+
2 + 6H + + 2e − 2Tc 3+ + 4H 2 O
0.316
TcO 2 + 2H + + e − TcO + + H 2 O
0.319
III/0
Tc 3+ + 3e − Tc
0.366
numerous thermodynamic and kinetic parameters related to technetium reactions in
solutions. Neverethless, the authors of this review made a critical analysis of the
literature data reported so far and they select and discuss the most reliable information on Tc chemistry, including the parameters in question. In order to summarize the
review, the redox potentials of the selected Tc couples are collected in Table 3.8. This
table also includes values not reported by the OECD Chemical Thermodynamics of
technetium.
References
Alberto R, Pak JK, van Staveren D et al (2004) Mono-, Bi-, or tridentate ligands? The labeling of
peptides with 99 mTc-carbonyls. Biopolym (Peptide Science) 76:324–333
Alliot I, Alliot C, Vitorge P et al (2009) Speciation of technetium(IV) in bicarbonate media. Environ
Sci Technol 43:9174–9182
Armstrong R, Taube H (1976) Chemistry of trans-Aquontrosyltetraamminetechnetium(I) and
related studies. Inorg Chem 15(8):1904–1909
Astheimer L, Schwochau K (1976) Electrochemical reduction of MnO
−
4 , TcO
−
4 and ReO
−
4 in organic
solvents: preparation of tetraoxomanganate(VI), -technetate(VI) and -rhenate(VI). J Inorg Nucl
Chem 38(6):1131–1134
Astuti Y, Topoglidis E, Gilardi G et al (2004) Cyclic voltammetry and voltabsorptometry studies of
redox proteins immobilized on nanocrystalline tin dioxide electrodes. Bioelectrochem 63:55–59
Balasekaran SM, Spandl J, Hagenbach A et al (2014) Fluoridonitrosyl complexes of technetium(I)
and technetium(II). Synthesis, characterization, reactions, and DFT calculations. Inorg Chem
53:5117–5128
63
Table 3.8 Standard reduction potential of selected technetium red–ox couples (values with
uncertainties given are recommended in Rard et al. 1999 and later updates)
Oxidation states of Tc Redox reaction
E ⦵ /V
VII/VI
TcO
−
4 + e − TcO
2−
4
−0.64 ± 0.03
VII/V
TcO
−
4 + 2e − TcO
3−
4
−0.60 ± 0.05
VII/IV
TcO
−
4 + 4H + + 3e − TcO 2 · xH 2 O(s) + (2 − x)H 2 O 0.746 ± 0.012
2TcO
−
4 + 10H + + 6e − Tc 2 O 2 (OH)
2+
2 + 4H 2 O
0.731 ± 0.011
TcO
−
4 + 6H + + 3e − TcO 2+ + 3H 2 O
0.660
TcO
−
4 + 4H + + 3e − TcO(OH) 2 (aq) + H 2 O
0.595 ± 0.046
VII/III
TcO
−
4 + 8H + + 4e − Tc 3+ + 4H 2 O
0.576
VII/0
TcO
−
4 + 8H + + 7e − Tc + 4H 2 O
0.472
IV/III
TcO(OH) 2 (aq) + 4H + + e − Tc 3+ + 3H 2 O
0.516
Tc 2 O 2 (OH)
2+
2 + 6H + + 2e − 2Tc 3+ + 4H 2 O
0.316
TcO 2 + 2H + + e − TcO + + H 2 O
0.319
III/0
Tc 3+ + 3e − Tc
0.366
numerous thermodynamic and kinetic parameters related to technetium reactions in
solutions. Neverethless, the authors of this review made a critical analysis of the
literature data reported so far and they select and discuss the most reliable information on Tc chemistry, including the parameters in question. In order to summarize the
review, the redox potentials of the selected Tc couples are collected in Table 3.8. This
table also includes values not reported by the OECD Chemical Thermodynamics of
technetium.
References
Alberto R, Pak JK, van Staveren D et al (2004) Mono-, Bi-, or tridentate ligands? The labeling of
peptides with 99 mTc-carbonyls. Biopolym (Peptide Science) 76:324–333
Alliot I, Alliot C, Vitorge P et al (2009) Speciation of technetium(IV) in bicarbonate media. Environ
Sci Technol 43:9174–9182
Armstrong R, Taube H (1976) Chemistry of trans-Aquontrosyltetraamminetechnetium(I) and
related studies. Inorg Chem 15(8):1904–1909
Astheimer L, Schwochau K (1976) Electrochemical reduction of MnO
−
4 , TcO
−
4 and ReO
−
4 in organic
solvents: preparation of tetraoxomanganate(VI), -technetate(VI) and -rhenate(VI). J Inorg Nucl
Chem 38(6):1131–1134
Astuti Y, Topoglidis E, Gilardi G et al (2004) Cyclic voltammetry and voltabsorptometry studies of
redox proteins immobilized on nanocrystalline tin dioxide electrodes. Bioelectrochem 63:55–59
Balasekaran SM, Spandl J, Hagenbach A et al (2014) Fluoridonitrosyl complexes of technetium(I)
and technetium(II). Synthesis, characterization, reactions, and DFT calculations. Inorg Chem
53:5117–5128