CONTRIBUTIONS TO ACCURACY IMPROVEMENT OF SIMULTANEOUS ICP ATOMIC-EMISSION SPECTROMETRY USING MULTI-LINE MEASUREMENTS OF ANALYTE AND INTERNAL STANDARD ELEMENTS - APPLICATIONS FOR THE ANALYSIS OF PERMALLOY

For successful application of simultaneous ICP atomic emission spectro metry for major component determinations in multi-component materials the accuracy of the method has to be improved. As a contribution to so lve this problem a combined procedure for multi-component standard sam ple preparation, optimum calibration and different variations of inter nal standard corrections is described. Variance-weighted multi-line ca librations give most accurate results. Internal standard corrections a re effective, if the time-dependent spectral line intensity fluctuatio ns of the standard and the analyte elements are well correlated. Their sensitivities against some responsible device parameter variations ar e investigated. On the basis of multi-line measurements of the analyte and internal standard elements a ''group-selected internal standard c orrection'' (GS-ISC) method is applied and results in relative errors of less than 1% even for extreme fluctuations of the raw intensities. For rapid routine determination methods of materials with variable ele ment compositions the added line intensities of the internal standard element can be used to correct the added analyte line raw intensities (''intensity addition internal standard correction'' (IA-ISC) method). These accuracy optimization procedures are applied for the analysis o f the soft magnetic material permalloy using the internal standard ele ment In.