Figure 3: Absorption spectra of (i) Unpromoted reaction mixture (after completion of reaction): (DMSO)T=75 × 10-4 mol dm-3, (Cr(VI))T=5 × 10-4 mol dm-3, (H2SO4)T=0.5 mol dm-3 (The spectrum of the chromic sulfate is identical with this under the experimental condition). (ii) Promoted reaction mixture (after completion of reaction): (DMSO)T=75 × 10-4 mol dm-3, (Cr(VI))T=5 × 10-4 mol dm-3, (H2SO4)T=0.5 mol dm-3, (phen)=25 × 10-4 mol dm-3.