INFLUENCE OF AN ELECTRIC-FIELD ON THE EMISSION AND ABSORPTION OF ATOMS AND IONS IN A FLAME

Experiments were carried out to explore the effect of an electric fiel d upon atomic species introduced into a flame. The study involves comp onents from a conventional flame atomic absorption apparatus with 10 x 10-cm parallel plate electrodes as the cathode and the 5-cm slot burn er head as the anode. A marked decrease in the emission and absorption of many atomic species was observed, and quantification of the effect was carried out. The effect has been interpreted as a disturbance of the equilibrium, Me <----> Me(+) + e(-). Relative decreases in absorpt ion and emission were found to be functions of applied voltage and ana lyte concentration at low voltages, and constant for high voltages (ap proximate to -2000 V). Temporal behavior of the effect has been invest igated by observation of the speed of restoration of the emission sign al from Na (589.16 nm), Sr (460.86 nm); and Sr+ (407.89 nm) after rapi d elimination of the electric field. The effects were also studied as a function of viewing position in the flame for optimization of the po sition and comparison of the temporal behavior with the speed of the f lame gases.