Sulfate Speciation Analysis Using Soft X-ray Emission Spectroscopy

The chemical and electronic structures of 15 different sulfates are studied using S L-2,L-3 soft X-ray emission spectroscopy (XES). Sulfur L-2,L- 3 XES spectra of sulfates are distinctively different from those of other sulfur compounds, which makes XES a powerful technique for sulfate detection. Furthermore, subtle but distinct differences between the spectra of sulfates with different cations are observed, which allow a further differentiation of the specific compound. Most prominently, the position and width of the emission from S 3s derived bands systematically vary for different compounds, which can be understood with electronic structure and spectral calculations based on density functional theory.

Automated summary

The chemical and electronic structures of 15 different sulfates were studied using S L-2, L-3 soft X-ray emission spectroscopy (XES). The sulfur L-2, L-3 XES spectra of sulfates are distinct from those of other sulfur compounds, making XES a powerful technique for sulfate detection. Subtle but distinct differences between the spectra of sulfates with different cations are observed, allowing for further differentiation of specific compounds. Most notably, the position and width of the emission from S 3s derived bands systematically vary for different compounds, which can be understood through electronic structure and spectral calculations based on density functional theory.