Laser ablation molecular isotopic spectrometry (LAMIS) recently was reported for rapid isotopic analysis by measuring molecular emission from laser-induced plasmas at atmospheric pressure. This research utilized the LAMIS approach to study C2 molecular formation from laser ablation of carbon isotopic samples in a neon gas environment at 0.1 MPa. The isotopic shift for the Swan system of the C2 Δν = 1 band was chosen for carbon isotope analysis. Temporal and spatial resolved measurements of 12C2, 12C13C, and 13C2 show that C2 forms from recombination reactions in the plasma. A theoretical simulation was used to determine the temperature from the molecular bands and to extract the isotopic ratio of 12C/13C derived from 12C2, 12C13C, and 13C2. Our data show that the ratio of 12C/13C varies with time after the laser pulse and with distance above the sample. 12C/13C deviates from the nominal ratio (2:1) at early times and closest to the sample surface. These measurements provide understanding of the chemical processes in the laser plasma and analytical improvement using LAMIS.
BT - Analytical Chemistry DA - 03/2013 DO - 10.1021/ac303524d IS - 5 N2 -Laser ablation molecular isotopic spectrometry (LAMIS) recently was reported for rapid isotopic analysis by measuring molecular emission from laser-induced plasmas at atmospheric pressure. This research utilized the LAMIS approach to study C2 molecular formation from laser ablation of carbon isotopic samples in a neon gas environment at 0.1 MPa. The isotopic shift for the Swan system of the C2 Δν = 1 band was chosen for carbon isotope analysis. Temporal and spatial resolved measurements of 12C2, 12C13C, and 13C2 show that C2 forms from recombination reactions in the plasma. A theoretical simulation was used to determine the temperature from the molecular bands and to extract the isotopic ratio of 12C/13C derived from 12C2, 12C13C, and 13C2. Our data show that the ratio of 12C/13C varies with time after the laser pulse and with distance above the sample. 12C/13C deviates from the nominal ratio (2:1) at early times and closest to the sample surface. These measurements provide understanding of the chemical processes in the laser plasma and analytical improvement using LAMIS.
PY - 2013 SP - 2899 EP - 2906 ST - Anal. Chem. T2 - Analytical Chemistry TI - Carbon Isotope Separation and Molecular Formation in Laser-Induced Plasmas by Laser Ablation Molecular Isotopic Spectrometry VL - 85 SN - 0003-2700 ER -