Systematics of multielement determination with resonance ionization mass spectrometry and thermal atomization

The systematics for multielement determination using resonance ionization mass spectrometry and thermal atomization is developed. The aspects of atomization, ionization, and detection are discussed and resonance ionization is demonstrated for 19 elements. The selective, sequential ionization of seven elements from a single sample is also demonstrated. A one-wavelength, two-photon ionization scheme generally is used in which the first photon excites a bound transition in the near-ultraviolet region and second photon promotes the electron into theionization continuum. The wavelength-dependence ion formation from the thermally produced atom reservoirs is demonstrated for these elements by scanning a Nd:YAG-pumped dye laser across its tunable wavelength range. The observed wavelengths where ionization occurs have been correlated where possible with allowed transitions between known electronic energy levels. The elements accessible by using four common dyes are tabulated. More than 20 elements are accessible within the wavelength range of each dye