ANALYTICAL LASER ENHANCED IONIZATION STUDIES OF THALLIUM IN THE AIR - ACETYLENE FLAME
Analytical studies are presented for the determination of thallium at ultratrace levels in the air - acetylene flame by means of laser enhanced ionization spectrometry. Two excimer pumped tunable dye lasers were used. Several transitions were investigated and compared in terms of detection limits. An enhancement factor of 38 was obtained by exciting at 291.832 nm and using a second photon at 377.572 nm or at 276.787 nm to indirectly increase the population of the metastable 2-P-3/2 level. At a repetition frequency of 50 Hz and with optimized filtering, the detection limit was found to be 8 pg/ml, therefore showing that the flame rivals the detection power achievable only by the use of electrothermal atomization. The technique has been applied to the direct determination of submicrogram per gram concentration levels of thallium in three commercial lead samples.
Bibliographic Reference: ANALYTICAL CHEMISTRY, VOL. 57 (1985), PP. 1256-1261
Record Number: 1989123107400 / Last updated on: 1987-01-01
Available languages: en