The carbonate, Co-3(-center dot) solution studied by resonance Raman spectroscopy

The carbonate radical (CO3-.) is of biological significance acting as an in termediate in free radical-mediated damage and is capable of oxidising amin o acids and proteins. In order to distinguish between the four possible str uctures of CO3-., nanosecond time-resolved resonance Raman (TR3) experiment s were undertaken. Photolysis of persulphate at 250 nm generated the SO4-. radical which then oxidised sodium carbonate. Resonance Raman spectra of th e resulting CO3-. radical were obtained using a probe wavelength of 620 nm. Point group theory calculations and interpretation of the TR3 spectra sugg est that the radical has C-2 upsilon molecular symmetry.