Fallacies in deducing gas phase reactions in electrothermal atomization through the use of Arrhenius plots

Abstract

The use of Arrhenius-type plots employing the leading edge of the absorbance signal from electrothermal atomization to extract energetics of gas phase dissociation processes is likely in error. Because analytecontaining molecular species may be continuously generated and these same species lost by diffusion during the measurement period, erroneous data will result from using the slopes from Arrhenius-type plots. Simulations with known input energies of vaporization and enthalpies of dissociation are used in illustrating the errors that will occur from over interpreting the slopes derived from the curves. It is also apparent how one might “see” a straight line region where, in fact, none exists.