Crystalline structure and magnetic properties of pyrite FeS2

Abstract

Iron pyrite (FeS2) has attracted significant attention as a promising inorganic material in various applications, such as electrode materials for high-energy batteries, medical diagnostics, semiconductor materials, and photovoltaic solar cells. In this study, we characterized the crystalline structure and magnetic properties of FeS2 using X-ray diffraction (XRD), vibrating sample magnetometry, and Mössbauer spectroscopy. The refined XRD patterns confirmed that the crystalline structure of FeS2 was cubic (Pa-3 space group) with lattice constant a0 = 5.417 Å. The temperature dependence of the zero-field-cooled and field-cooled curves and the hysteresis loops were measured at various temperatures between 4.2 and 295 K. The Mössbauer spectra collected in the temperature range of 4.2–500 K were fitted with one doublet. The ΔEQ values increased slightly with decreasing temperature owing to changes in the Fe–S distance. The charge state was determined to be Fe2+ based on the isomer shift (δ).

Characterization of Microschist Rocks under High Temperature at Najran Area of Saudi Arabia

“…The obtained XRD peaks were matched with built-in standard mineral phases XRD-patterns in "PowderX" and "Match!" softwares, and also compared with published work [41,48,50,51]. The findings show that the studied microschist consists of quartz, albite, clinochlore, biotite, muscovite, epidote, pyrite, zoisite, rutile, and magnesite (Figure 12 and Table 2).…”

Synthetically Produced Isocubanite as an Anode Material for Sodium-Ion Batteries: Understanding the Reaction Mechanism During Sodium Uptake and Release

“…The value for the saturation magnetization M s was found to be 52.9 emu g –1 . This large value is just explainable with the presence of elemental iron due to the fact that neither iron sulfides − nor copper iron sulfides , or Cu exhibit such large M s values. The magnetic moment ( n B ) in Bohr magneton (μ B ), can be calculated by using the relation …”

Simplistic Approach for Determining Center Shift of Mössbauer Spectrum: Exemplified on Two Cases

“…Figure 1 presents three spectra recorded at different temperatures. Noteworthy, the doubletlike structure persists down to 4.2 K, but a significant line broadening is observed at low temperatures related to a weak magnetism of FeS 2 [9].…”

“…Unit cell of pyrite, FeS 2 , has a cubic symmetry but Fe atoms have a slightly distorted octahedral symmetry [9], hence they experience an electric field gradient.…”

“…Thus, Nishihara and Ogawa reported 610(15) K obtained from the analysis of CS(T) measured between 77 K and 292 K [12], Kansy et. al [13] found 568(20) K for a natural sample of FeS 2 based on the CS(T)-data measured in the T-range between 290 K and 430 K, Polyakov et al [11] measured a synthesized sample between 90 K and 295 K and using the CS(T)-data arrived at the value of 551(8.5) K. Finally, the value of T D =636(5) K was determined for a natural sample by analyzing the temperature dependence of the f-fraction [14]. It is obvious that the shape of the spectra is all but not well-resolved.…”