Simulation of atomic spectra—I. Profiles and signal-to-background ratios of 350 prominent lines emitted from an inductively coupled plasma or whatever “customized” atomic emission lines

Abstract

This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta B (SAB). The hardcopy text, comprising the main article and an appendix, is accompanied by a diskette with a program, data files, and a manual. The text details the purpose of the work, with emphasis on the spectrosopic aspects, and the appendix provides the essential information for accessing the diskette and using program and data. Additional tutorial guidance is provided by the manual. The program primarily concerns the simulation of the profiles of 350 prominent lines of 65 elements emitted from an inductively coupled plasma in dependence on the spectral bandwidth of the spectrometer and the Doppler temperature of the source as optional variables. The physical characteristics of the lines, including specific values of the a-parameter of the Voigt profile and data on hyperfine structure (HFS) are stored in the database. A spectrum is displayed in terms of (SBR + 1) as a function of wavelength, where SBR = signal-to-background ratio. A spectral window of 80 pm is covered. Additionally: numerical data are displayed, encompassing, inter alia, the SBR and background equivalent concentration (BEC) in the maximum of the spectral structure, the full width at half maximum (FWHM) of the structure, and “standard” values of SBR, BEC, and detection limit, stored in the computer. The prime purpose of the program is to facilitate the conversion of data on SBRs, BECs, and detection limits between instruments of different spectral bandwidth and thus to ease unbiased comparisons between different ICPs or between ICPs and other sources. The database, which covers both simple lines and complex HFS composites, has been derived from the data reported by Boumans and Vrakking [ Spectrochim. Acta 41B, 1235 (1986)]. Vast improvements in the data resulted from the interactive development of the program and the database. The relevant studies as well as the development and testing of various models for handling HFS composites are detailed in the hardcopy text. These studies may be reworked using the program and an additional, small, dedicated database. The tutorial part of the manual provides the user not only with elementary instructions for using the program as a practical tool, but also incorporates a variety of instructive examples, including a brief “course” on spectral line profiles. The approach leaves many possibilities for customization of spectral lines, since both the data files for the individual spectral lines as well as the umbrella files for all lines grouped in a database have a simple and transparent organization: users may thus easily add customized files to the existing databases or generate new databases for whatever purposes.