Theory of analytical curves in atomic fluorescence flame spectrometry

Abstract

An explicit expression for the intensity of atomic resonance fluorescence as a function of atomic concentration in a flame is derived under certain idealized conditions. The expression is generally valid for a pure Doppler absorption line profile as well as for a combined Doppler and collisional broadened profile (Voigt profile) of the absorption line in the entire range of concentration values.

The expression derived was used to calculate analytical curves for a number of different values of the ratio of collisional line width to Doppler width. The calculations were carried out for a single resonance line in the extreme cases of a very narrow exciting line source and a continuum radiation source, respectively.

Furthermore, a method is given to determine the so called damping parameter “a” and the fluorescence yield factor p from the asymptotic behaviour of the analytical curves if the actual atomic flame content at the intersection point of the initial and final asymptote is calibrated.