THEORETICAL PRINCIPLES OF INTERNAL STANDARDIZATION IN ANALYTICAL EMISSION SPECTROSCOPY

The principles which affect the choice of analysis and internal standard lines in analytical atomic spectroscopy are explored theoretically using a computer-based model. The spectral source chosen for the model was the induction-coupled argon plasma fed with a water solution of metallic salts. The effect of excitation energy, ionization energy, partition functions and electron density on the analytical line pair intensity ratio is explored. Examples are presented which illustrate the contribution of each variable to the intensity ratio over the 3000-15000°K temperature range, allowing the reader to assess the importance of each based on a knowledge of the properties of his own source. Finally, some of the problems encountered in the course of this study are discussed. © 1968.