Isotope shift of the 3s2S12 and 3p2PJ levels in 6,7Li

A semiconductor diode laser spectrometer for laser spectrochemistry

Measurements of rubidium in standard reference samples by wavelength-modulation diode laser absorption spectrometry in a graphite furnace

Measurement of 7Li/6Li isotope ratios by resonant Doppler-free two-photon diode laser atomic absorption spectroscopy in a low-pressure graphite furnace

Resonant two-photon absorption spectroscopy with laser diodes is applied for isotope selective analysis of 6 Li and 7 Li in a low-pressure graphite furnace atomizer. The detection limits for both isotopes and the selectivity in form of the relative absorption sensitivity for 6 Li are determined under large optical saturation conditions with co-propagat- ing laser beams as well as for small optical saturation with counter-propagating beams. The influence of collisional energy transfer and radiative processes are studied and taken into account. Absolute detection limits lower than 1 pg are found for both isotopes. The selectivity for 6 Li is approximately 4.8= 10 3 in the high saturation and approximately 4.6= 10 4 in the low saturation case. The isotope ratio of a highly 7 Li enriched stock solution was measured and found to agree with previous results obtained by wavelength modulation diode laser atomic absorption spectrometry of the Li resonance lines. Q 2000 Elsevier Science B.V. All rights reserved.

C. Vadla

Papers

Measurement of velocity dependence of collisional excitation transfer applying resonant doppler-free 2-photon laser spectroscopy