Singlet Molecular Oxygen

Photosensitized oxidations involving singlet oxygen are implicated in photodynamic inactivation of viruses and cells, in phototherapy for cancer, in photocarcinogenesis and in photodegradation of dyes and polymers. Quenching of excited singlet and triplet states of many substances by ground state molecular oxygen produces singlet oxygen, the lowest electronically excited singlet state of molecular oxygen. The fractions of singlet and triplet states quenched which produce singlet oxygen and the quantum yields of formation of singlet oxygen in fluid solutions have been critically compiled. Methods for determining yield parameters have been reviewed. Data have been compiled from the literature through 1991.

Data are tabulated for 754 substances, such as the following categories of photosensitizers.

• aromatic hydrocarbons
• aromatic ketones and thiones
• quinones
• coumarins
• fluoresceins
• transition metal complexes
• heterocyclics
• porphyrins and phthalocyanines
• dyes
• drugs

Published by:

Francis Wilkinson, W. Phillip Helman, and Alberta B. Ross
J. Phys. Chem. Ref. Data 22 113-262 (1993) __ Ordering info.

A related compilation of the rates of decay and reaction of singlet molecular oxygen was originally published in 1981 is is currently being updated.

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This document prepared by Ian Carmichael

Work supported by:

Office of Basic Energy Sciences
United States Department of Energy

Standard Reference Data
National Institute of Standards and Technology