SINGLET OXYGEN PRODUCTION FROM SINGLET AND TRIPLET-STATES OF 9,10-DICYANOANTHRACENE

The mechanism and quantum yield of singlet oxygen (O-1(2)) production by 9, 10-dicyanoanthracene (DCA) has been investigated in benzene and acetonitrile; O-1(2) is produced from both the singlet and triplet states of DCA. Intersystem crossing enhanced by 2,5-dimethyliodobenzene (DMIB) provided a direct route to 3DCA and allowed determination of the individual contributions of 3DCA and 1DCA to O-1(2) production. Enhanced intersystem crossing can make the triplet pathway a major route under some conditions and can result in high quantum yields of O-1(2).