LIBS Info: Element Analysis

Title	Authors	Material	Detector	Spectrometer
Correction of self-absorption effect in calibration-free laser-induced breakdown spectroscopy by an internal reference method	Lanziang Sun, Haibin Yu	Metal Alloys	Ocean Optics LIBS2500+	Ocean Optics LIBS2500+
Laser:	Nd:YAG 1064.0000nm 200.0000mJ 15.000Hz
Gate Delay:	Noneus
Gate Width:	1000.000us
The authors propose a modification to the standard (Saha-Boltzmann plot) Calibration Free LIBS to account for self absorption of peaks. This relies on a correction factor derived from a peak that is not expected to be self-absorbed (from a transition not ending the ground state for example). To account for the long integration time of the detectors, 2 groups of 100 spectra were collected for each sample at different delay times (2.5/5.0us for aluminium alloy, 0.83/4.17us for the iron alloys) and the difference spectra is analysed. For Al and Cu, where the ionic peaks were weak, the Saha equation was used to estimate to concentrations of the ions.

Element	Detection Limit (ppm)	Wavelength (nm)	Other Wavelengths (nm)	Calibration Method	Calibration Range (ppm)	Notes

Element	RMSE (ppm)	Wavelength (nm)	Calibration Method	Notes
Al	4300.0000 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.
Cr	13559.4985 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.
Mn	3400.0000 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.
Fe	16824.3871 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.
Ni	23100.0000 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.
Cu	8000.0000 ppm	-10.0000	Saha-Boltzmann CF LIBS	Uses correction factor to account for self absorption.