Mössbauer studies on magnetism in FeSe

Abstract

Iron selenide (FeSe) was used to investigate magnetic properties by using Mössbauer spectroscopy. The crystalline structure of the sample was found to be tetragonal and hexagonal with a 3c structure. The temperature-dependent magnetic susceptibility curve under 100 Oe confirmed the spin rotation temperature TS = 150 K. Based on the applied field dependent magnetization measurements up to 15 kOe at 295 K, the saturation magnetization and coercivity were found to be 8.03 emu/g and 357.40 Oe, respectively. The spin rotation process of the sample from the dependence temperature ZFC-FC curves occurs at approximately TS. The Mössbauer spectra below the Néel temperature (TN) were fitted with a doublet for the tetragonal phase and three sextets (A, B, and C sites) for the hexagonal phase. The spectrum was fitted to a single line at TN = 500 K. We also observed abrupt changes in Hhf and ΔEQ at the spin rotation temperature. The Fe charge states in the tetragonal and hexagonal phases are found to be ferric and highly covalent ferrous ion (or high-spin ferric), respectively.

Fast-Charging Degradation Mechanism of Two-Dimensional FeSe Anode in Sodium-Ion Batteries

“…As displayed in Figure b, the 57 Fe Mössbauer spectrum of FeSe-NS can be fitted into two sextets (Fe site 1 and Fe site 2) and a typical doublet (Fe site 3). Combining the isomer shift data in Table S2, it can be seen that all Fe sites of FeSe-NS are Fe 2+ , where Fe site 1 and Fe site 2 demonstrate antiferromagnetism and Fe site 3 has paramagnetism. , Hence, FeSe-NS exhibits intrinsic antiferromagnetism at 300 K (Figure c).…”

“…Combining the isomer shift data in Table S2, it can be seen that all Fe sites of FeSe-NS are Fe 2+ , where Fe site 1 and Fe site 2 demonstrate antiferromagnetism and Fe site 3 has paramagnetism. 32,33 Hence, FeSe-NS exhibits intrinsic antiferromagnetism at 300 K (Figure 2c).…”

Thermal conductivity and phonon anharmonicity of chemical vapor transport grown and mineral–FeS2single crystals: An optothermal Raman study

“…This appears to be a reliable physical picture for several reasons. First, the applied experimental temperature range is below the Debye temperature of pyrite (Schönbrunn crystal as 610, [ 3 ] 568 ± 20, [ 45 ] and 640 ± 5 K [ 46 ] ). Second, when the PDOS of the FeS 2 is inspected, the number of the PDOS at is much lower.…”

Synergistic adsorption of ethyl xanthate and butyl xanthate on pyrite surfaces: A DFT study

“…The separation process of pyrite is mainly based on flotation, mineral flotation is based on the difference in hydrophilicity of the mineral surface to achieve the separation of different minerals [3, 4], commonly used in the flotation of pyrite collector xanthate, dithiophosphate, and so on [5, 6], of which xanthate is the most important and most widely used collector in pyrite flotation [3, 7–9]. Therefore, in recent years, the mechanism of the action of xanthate on the mineral surface has received the attention of many researchers, mainly through Fourier transform infrared spectroscopy (FTIR) [8], x‐ray photoelectron spectroscopy (XPS) [1], secondary ion mass spectrometry (SIMS), x‐ray diffraction (XRD) [10], microcalorimetry [11], and other physicochemical means, and the majority of them believe that a single xanthate and pyrite metal xanthates and double xanthates are formed after interaction and the products are co‐adsorbed on the pyrite surface [12, 13]. However, with the development of quantum theory, the theoretical study of density functional theory (DFT) as a new method applied to the flotation process found that the action of reagents on the mineral surface is not only simple interactions between ions [9, 14, 15], but mainly the coordination between reagents and the mineral surface [1, 7, 11, 16].…”