Ultratrace Metal Analysis by Mass Spectrometry of Volatile Metal β-Diketonates

Abstract

The synthesis and characterization of several β-diketonates,^1–4 principally those of fluorinated derivatives of acetylacetone, has permitted a new method of trace analysis by conventional mass spectrometry. Conventional mass spectrometry has been severely limited for trace analysis of metals by the volatility of metal compounds which may be formed quantitatively. The more recently developed spark-source mass spectrometers are capable of vaporizing the most refractory metals and metal compounds. However, quantitative results are extremely difficult to obtain due to the wide range of kinetic energies of the ions produced in the spark source. Also samples must either be fabricated as conducting electrodes for the source, or mixed and compacted with a conducting material such as graphite, thereby introducing errors of mixing and contamination.