Old City Publishing/De Gruyter
In contrast to the photolysis of Cr(CO)3(C6H6) in nonhalogenated solvents, in which the products are CrL(CO)2(C6H6) in the presence of a donor L, or Cr(CO)6 and C6H6 if no donor is present, the photo-reaction in chloroform yields CrCl3. No significant portion of the reaction occurs through absorption of 254nm light by CHCl3• The quantum yield is 1.4, consistent with a mechanism in which several radicals are formed upon chlorination of the chromium, which then cause further decomposition of the reactant. In 24% CCl4, the reaction still occurs primarily through the excited state metal complex, but there is a solvent-initiated contribution, which is more significant the lower the reactant concentration. The quantum yield for the solvent-initiated pathway is 0.3 in 24% CCL4.
Leslianna Federici and Patrick E. Hoggard, “Kinetics of the photolysis of benzenetricarbonylchromium(0) in chloroform”, Inorg. React. Mech. 2, 179-184 (2000).