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G. Ghosh, S. Moi, S. Panja, W. Linert:
"Kinetics and Mechanism of the Interaction of Thiosemicarbazide with Di-µ-hydroxobis(1,10-phenanthroline)di-paladium(II) ions in Aqueous Solution";
Synthesis and Reactivity in Inorganic Metal-Organic and Nano-Metal Chemistry, 41 (2011), 15 - 21.

The kinetics and mechanism of the interaction between
thiosemicarbazide with di-μ-hydroxobis(1,10-
phenanthroline)dipalladium(II) ion complex has been followed
spectrophotometrically in pseudo first order conditions in aqueous
solution as a function of [Pd(1,10-phen)(H2O)2]2+, [thiosemicarbazide],
pH, and temperature. The reaction of thiosemicarbazide
(TSC) at pH 6.5 has been monitored at λmax 240 nm. The
reaction rate increases linearly with increasing thiosemicarbazide
concentration in the studied concentration range. The second
order rate constants 102k2 are 27.01, 33.78, 40.23, and 50.46
dm3 mol−1 s−1 at 20, 25, 30, and 35◦C, respectively, have been
calculated from the slope of k(obs) versus [thiosemicarbazide]
plot by using the Origin6.0 software. From the experimental
findings, an associative mechanism for the substitution reaction
is proposed. The activation parameters calculated from Eyring
equation are H#1
= 46.72 ± 1.8 kJ mol−1, S#1
= −100.38 ±
3.1JK−1mole−1support the proposition. On the basis of the
kinetic and activation parameters, an associative mechanism
is proposed for the interaction process. Quantum chemically
obtained structures and geometrical parameters of the Pd(II)
complex have been reported.

1, 10-phenanthroline, associative mechanism, hydroxo bridged palladium(II) complex, kinetics and mechanism, thiosemicarbazide, quantum chemical calculation

http://dx.doi.org/10.1080/15533174.2010.522668