Comparison of 193, 213 and 266 nm laser ablation ICP-MS

There is a widespread discussion concerning the 'better' wavelength for laser ablation chemical analysis. Wavelength is believed to be an important parameter based on the sample's optical penetration depth as well as photon energy for bond breaking. The lasers most widely employed for analytical applications are the excimer, based on an ArF mixture with a wavelength of 193 nm, and the solid state Nd: YAG, with wavelengths of 266 nm and 213 nm. NIST glasses were ablated to test the effects of these wavelengths on fractionation and transport efficiency. Crater geometry and volume were measured by using a white-light interference microscope. For all three wavelengths, linear calibration curves were obtained using NIST glasses as standards. The Pb-208/U-238 ratio in a tuff rock sample was measured using all three wavelengths; the value obtained using the NIST-glass calibration was compared to that measured using liquid nebulization.