Linkage isomer ratios in thermal and photochemical anation of acidopentacyanocobaltate(III) anions

Abstract

Photolysis of [Co(CN) 5 X] n− ions, where X=CN − , N 3 − , Cl − , Br − , I − , OH − , and H 2 O, in slightly acidic aqueous thiocyanate solution has been found to give the linkage isomers of [Co(CN) 5 (CNS)] 3− , together with larger amounts of [Co(CN) 5 (H 2 O)] 2− . Photolyses at pH 13 and room temperature, and in acidic medium at −4 o C, demonstrate that direct photoanation occurs in competition with the more efficient aquation reaction