A Mechanism for Non-Flame Atomization in Atomic Absorption Spectroscopy

A mechanism for atom formation in non-flame atomizers, used in atomic absorption spectrophotometry, is presented. The model assumes that gas-phase metal atoms are produced by the direct thermal reduction of metallic oxides, produced as intermediates in the carbon furnace. This mechanism does not assume that carbon is involved in the reduction step. The minimum appearance temperatures for 15 elements are calculated from equilibrium atom concentrations and free energy data. The calculated appearance temperatures are found to correlate with the experimentally determined values for these elements.