Sulfur- and phosphorus- Kβ spectra analyses in sulfite, sulfate and phosphate compounds by X-ray fluorescence spectrometry

Abstract

Several sulfite, sulfate and phosphate compounds were studied by X-ray fluorescence spectrometry. Sulfur- and phosphorus- Kβ spectral profile modified by the number of bonding hydrogen and oxygen atoms were analyzed. As it could be confirmed, the molecular orbital theory provides a suitable explanation of the origin and properties of the satellite Kβ′ lines. Also, for the compounds analyzed, it was found that sulfur- and phosphorus- Kβ spectra present two main components and two secondary ones which exhibit a different behavior depending on the number of bonding hydrogen and oxygen atoms. Particularly, the peak corresponding to satellite Kβ′ line increases its intensity and moves away from the main peak when the number of oxygen atoms combined with the sulfur atom is increased. The energy differences between the main peak and the satellite peak found in the analyzed compounds were in average 14.2±0.4 eV, thus being demonstrated that such a separation is a characteristic of the bonding atom, in this instance oxygen.