Description of a computer program for quantitative spectral analysis of ICP-AES spectra generated with a high resolution computer-controlled monochromator

Abstract

A FORTRAN computer program is described performing automatic quantitative spectral analysis on spectral windows (approximately 15 experimental effective line widths wide) obtained with scans from a high resolution computer-controlled monochromator, using short integration times on each wavelength position (e.g. 250 ms). This program quantifies the net analyte signal from the measurements in the relevant spectral region, whereby all possible contributions from the background and/or interfering lines are considered. This artificial intelligence obviates all operator descisions with respect to background correction and spectral interference correction. The article gives a detailed description of how this program works and discusses the following topics: smoothing of raw data, peak detection, background correction, test for spectral interference and correction of most spectral interferences, and calculation of the final net signal and its standard deviation. The present program enables accurate analyses of samples without any prior knowledge of sample composition and requires the utmost minimum of operator-software interaction. The dependency on instrument specific parameters is limited to a single value, viz. the average experimental effective line width. As all essential spectral information is condensed in the final output and is accompanied by appropriate warning messages, a diagnosis can be easily made in the event of abnormalities. The combination of the proposed measurement mode and accompanying spectral analysis is evaluated and compared with the classical three point (longer integration time) measurement modes with respect to detection power, accuracy, speed and user-friendliness.