US EPA

1628491 

Journal Article 

Chemical actinometry 

Kuhn, HJ; Braslavsky, SE; Schmidt, R 

2004 

1 

Pure and Applied Chemistry
ISSN: 0033-4545
EISSN: 1365-3075 

76 

12 

2105-2146 

WOS:000226560100006 

This document updates the first version of the IUPAC
technical report on ""Chemical actinometers"" published in Pure Appl. Chem. 61, 187-210 (1989).
Since then, some methods have been improved, procedures have been modified, and new substances
have been proposed as chemical actinometers. An actinometer is a chemical system or a physical
device by which the number of photons in a beam absorbed into the defined space of a chemical
reactor can be determined integrally or per time. This compilation includes chemical actinometers
for the gas, solid, microheterogeneous, and liquid phases, as well as for the use with pulsed
lasers for the measurement of transient absorbances, including the quantum yield of
phototransformation, as well as the literature for each of the actinometers. The actinometers
listed are for the use in the wavelength range from the UV to the red region of the spectrum. A
set of recommended standard procedures is also given. Advantages and disadvantages are discussed
regarding the use of chemical actinometers vs. electronic devices for the measurement of the
number of photons absorbed. Procedures for the absolute measurement of incident photon flux by
means of photodiodes are also discussed.