Pulsed-laser photochemical study of tris(1,10-phenanthroline)chromium(III) ion in acidic and alkaline aqueous media

Photochemistry and Photophysics of Chromium(III) Complexes

“…For Cr(III) complexes that show the same quantum yield of photochemistry on doublet and quartet irradiation, it can be inferred that the overall reaction efficiency via the doublet and quartet states is the same and the fraction of the reaction that occurs via the doublet state equals φ D . From conductivity monitoring experiments, ,,, it is 0.68 for Cr(en) 3 3+ , in excellent agreement with the values from the direct methods. These studies also gave 157 the values 0.74 for Cr(NH 3 ) 5 (CN) 2+ in agreement with the 0.73 value 95 from quenching experiments, 0.77 for Cr(NH 3 ) 5 (NCS) 2+ , 1.0 for trans- Cr(en) 2 F 2 + , and >0.93 for Cr(bpy) 3 3+ .…”

“…The laser flash photolysis studies with conductivity detection 124,125 allowed comparison of the kinetic behavior of Cr(bpy) 3 3+ and Cr(phen) 3 3+ . These authors found that for Cr(bpy) 3 3+ , about 93% of the reaction occurred via the doublet state.…”