Supplementary Information
Oxidation of Ru(III)-bound Thiocyanate with Peroxomonosulfate. Kinetic and
Mechanistic Studies
PAPIYA SARKAR AND DEBABRATA CHATTERJEE*
S1
Experimental Procedures Micro-analysis and spectral data for [RuIII(Hedta)Cl].
2H2O complex
K[RuIII(Hedta)Cl]·2H2O was prepared by following the published procedure and
characterized accordingly. K2[RuCl5(H2O)] (1 mmol) was reacted with Na2H2edta (1 mmol) in
HClO4 (1 mM). The reaction mixture was refluxed for 2 h and the volume of the pale-yellow
solution was then reduced. Addition of cold ethanol precipitated the pale-yellow product, which
was filtered off and washed several times with a water–acetone (1:9) mixture until free of
chloride, and finally dried under vacuum. Anal. calculated for K[RuIII(Hedta)Cl].2H2O: C 24.0,
H 3.42, N 5.59; Found. C 23.8, H 3.45, N 5.63. IR, ν/cm-1: 1720 (free -COOH), 1650
(coordinated -COO-). UV-Vis in H2O: λmax/nm (εmax/M-1 cm-1): 283 (2800  50), 350 sh (680 
10).
0.25
Absorbance at 450 nm
0.20
0.15
0.10
0.05
0.00
0.0
0.2
0.4
0.6
0.8
1.0
-
[HSO5 ], mM
Figure S1 Results of stoichiometric studies for the reaction of [RuIII(edta)(SCN)]2- with HSO5- at
25 C and pH 6.2 (phosphate buffer). [RuIII] = 0.2 mM. Observed increase in absorbance at 450
nm at [HSO5-] > 0.4 mM is attributed due to the formation of the band at 390 nm, i.e. formation
of [RuV(edta)O]- in reaction (as seen in Fig.S2).
Figure S2 Spectral changes that occurs in the prolonged reaction of [Ru III(edta)(SCN)]2- with
HSO5- at 25 C and pH 6.2 (phosphate buffer). [RuIII] = 0.1 mM and [HSO5-] = 5.0 mM.
Formation of [RuV(edta)(O)]- is evidenced by the development of the peak at 390 nm.
Absorbance at 390 nm
0.16
0.12
0.08
Experimentally obtained
Simulated
0.04
0.00
0
100
200
300
400
500
time (sec)
Figure S3 Experimental (black) and simulated (red) absorbance–time traces at 390 nm for the
reaction of [RuIII(edta)(SCN)]2- with a fixed excess of HSO5-. Experimental conditions: [RuIII] =
0.2 mM, [SCN-] = 2 mM, [HSO5-] = 5 mM, pH 6.2 (phosphate buffer) and temperature 25 C.