Sulfur K x-ray absorption spectra of FeS, FeS2, and Fe2S3

Abstract

The K absorption spectra of sulfur in FeS, FeS2 (pyrite), and Fe2S3 have been measured with a 50 cm bent-quartz-crystal vacuum spectrograph. The spectra of FeS and Fe2S3 are similar to each other but are fairly different from that of FeS2. The FeS2 spectrum is discussed in terms of two theoretical calculations: the energy band for FeS2 (pyrite) and the molecular orbital (MO) of the S22− ion. The spectra for FeS and Fe2S3 are explained by the application of Terakura’s theory and the first absorption band is attributed to the transitions to the empty antibonding states formed by the redistribution of the sulfur 3p bands under the influence of the iron 3d bands.

The oxidation states of copper and iron in mineral sulfides, and the oxides formed on initial exposure of chalcopyrite and bornite to air

“…10. Apart from that for chalcocite, the experimental spectra are generally in good agreement with the corresponding spectra reported previously, such as those by Sugiura (1981), Petiau et al (1988), Li et al (1994Li et al ( , 1995, Mosselmans et al (1995), Pattrick et al (1997), Lavrentyev et al (2004) and von Oertzen et al (2005.…”

X-ray absorption near-edge spectra of transition metal disulfides FeS2 (pyrite and marcasite), CoS2, NiS2 and CuS2, and their isomorphs FeAsS and CoAsS

“…K-edge XAS spectra of pyrite have been previously published (Sugiura 1981(Sugiura , 1984Petiau et al 1988), as have the L-edge spectra of FeS2 (Thole andvan der Laan 1988) andCuS2 (van der Laan et al 1992). Here, we report for the first time the complete set of metal K-and L3-edge, sulfur K-edge and arsenic K-and L3-edge spectra of FeS2 (pyrite and marcasite) COS2, NiS2, CuS2, FeAsS and CoAsS.…”

Hard X-ray photoelectron and X-ray absorption spectroscopy characterization of oxidized surfaces of iron sulfides

“…The XAS spectra of NiAs-structured pyrrhotite and stoichiometric troilite FeS have been measured, calculated and analyzed in a number of studies; the spectroscopic features are largely similar to those in pyrite, despite different electronic structures, and their detailed description can be found in the literature [43][44][45][46][47][48][49][50][51][52][53][54][55][56]. The main differences observed in the S K-edge XANES (Fig.…”

“…the Fe K-edge spectra are commonly attributed to electron transitions from the core Fe 1 s to vacant Fe 3d e g states mixed with Fe 4p and with S 3p * states (1 s-3d transitions are forbidden by dipole selection rules) [43][44][45][46][47][48]. The resonances c correspond to Fe 4p,s states mixed with S 3p * orbitals; the peak d is due to transition to Fe 4p,s states [43][44][45][46][47][48], and the feature e can be assigned to transitions to atomic S 3p orbitals and multiple scattering resonances [45] or Fe 4sp-S 3d states [60]. The Fe K-edge XANES measured in the PFY mode do not change as a result of oxidation and etching and correspond to the bulk pyrite.…”

“…A number of XANES studies on iron sulfides have been reported previously [33,[43][44][45][46][47][48][49][50][51][52][53][54][55][56], but the difference between TEY and PFY Kedge spectra of air-oxidized and chemically etched materials has not been analyzed yet. Here, samples of each mineral (i.e., pyrite and pyrrhotite) polished in air were compared with those treated with an acidic ferric chloride solution to probe the effect of exposure to the leaching (etching) medium in hydrometallurgy and natural environments, and in materials science.…”