Energy transfer from sensitizer singlet states

As a consequence of energy transfer from excited singlet state or triplet state of a sensitizer to molecular oxygen may be formeds <, ... 

The production of 02 has been reported to occur by energy transfer from the singlet- and triplet-excited states of the sensitizer, but that from the triplet excited state is highly preferred because singlet-triplet interaction is of very low probability. The lifetime of 02 is highly dependent on the solvent medium and the presence of scavengers or oxidizable acceptors it was determined to be about 3.1 x 1(T6 s in water (Rodgers and Snowden, 1982) and 50 to 100 x 106 s in lipid (Henderson and... 

Energy transfer from singlet or triplet states of suitable organic molecules can cause excitation of the central metal ion in a coordination compound. Photosensitization of Cr(III) complexes by biacetyl leads to aquation reaction of Cr(NH3)5 (NCS)2 ion. The aquation of (NH3) is hundred times more than that of (NCS) for the sensitized reaction, whereas it is only 66 times on direct excitation of Cr(IlI). This shows that energy... 

Photochemical sources. One of the most common sources of singlet oxygen is energy transfer from an excited sensitizer (Sens), such as a dye or natural pigment, to the ground state of the oxygen molecule. The role of the sensitizer is to absorb irradiation and be converted to an electronically excited state (Sens ). This state, normally a triplet, then transfers its... 

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