Iron and Sulfur Isotope Factors of Pyrite: Data from Experimental Mössbauer Spectroscopy and Heat Capacity

V. B. Polyakov; E. G. Osadchii; M. V. Voronin; V. O. Osadchii; L. V. Sipavina; D. A. Chareev; A. V. Tyurin; V. M. Gurevich; K. S. Gavrichev

doi:10.1134/S0016702919040098

Iron and Sulfur Isotope Factors of Pyrite: Data from Experimental Mössbauer Spectroscopy and Heat Capacity

Authors: Polyakov V.B.¹, Osadchii E.G.¹, Voronin M.V.¹, Osadchii V.O.¹, Sipavina L.V.¹, Chareev D.A.¹^,2^,3, Tyurin A.V.⁴, Gurevich V.M.⁴^,5, Gavrichev K.S.⁴
Affiliations:
1. Korzhinckii Institute of Experimental Mineralogy (IEM), Russian Academy of Sciences
2. Eltsin Ural Federal University
3. Kazan Federal University
4. Kurnakov Institute of General and Inorganic Chemistry (IONKh), Russian Academy of Sciences
5. Vernadsky Institute of Geochemistry and Analytical Chemistry (GEOKhI), Russian Academy of Sciences
Issue: Vol 57, No 4 (2019)
Pages: 369-383
Section: Article
URL: https://journals.rcsi.science/0016-7029/article/view/156116
DOI: https://doi.org/10.1134/S0016702919040098
ID: 156116

Cite item

Full Text

Open Access
Restricted Access

Access granted
Restricted Access

Subscription Access

Abstract
About the authors
References
Supplementary files
Statistics

Abstract

Mössbauer spectra of pyrite (FeS₂) are measured within a temperature range of 90–295 K. The isomer shift is described by the Debye model with a Mössbauer temperature θ_M = 551.4 K. These results are used to calculate the kinetic energy of thermal vibrations of the iron sublattice of pyrite and the iron β-factor for pyrite: 10³\({\text{ln}}{{\beta }_{{^{{{\text{57}}}}{\text{Fe}}{{{\text{/}}}^{{{\text{54}}}}}{\text{Fe}}}}}\) = (1.2665 ± 0.0391)x – (0.4584 ± 0.0283) × 10^–2x² + (0.2581 ± 0.0239) × 10^–4x³; x = 10⁶/T ² (K^–2). The calculated iron β-factor in pyrite is in good agreement with results of ab initio calculations, ⁵⁷Fe nuclear inelastic X-ray resonant scattering in synchrotron experiments, and direct isotope exchange experiments between pyrite and Fe²⁺ dissolved in water. The heat capacity of pyrite is measured within a temperature range of 79–300 K and is described using the Thirring expansion. Based on this expansion, the kinetic energy of thermal vibrations of the total crystalline lattice of pyrite is calculated. The kinetic energy of the thermal vibrations of the sulfur sublattice in pyrite is found by subtracting the kinetic energy of the iron sublattice from the total kinetic energy of pyrite crystalline lattice. The temperature dependence of ³⁴S/³²S β-factor for pyrite, which was calculated from the kinetic energy of the sulfur sublattice, is 10³\({\text{ln}}{{\beta }_{{^{{{\text{34}}}}{\text{Fe}}{{{\text{/}}}^{{{\text{32}}}}}{\text{Fe}}}}}\) = (1.7532 ± 0.0623) x – (1.0470 ± 0.0752) × 10^–2x² + (1.0424 ± 0.1126) × 10^–4x³; x = 10⁶/T² (K^–2). This value of the ³⁴S/³²S β-factor is in good agreement with the ab initio calculations and with results of isotope-exchange experiments in the pyrite–sphalerite–galena system.

Keywords

pyrite, iron and sulfur isotope fractionation, β-factors of iron and sulfur for pyrite, pyrite Mössbauer spectrum, heat capacity of pyrite

Supplementary files

Supplementary Files

Action

1. JATS XML

Download

Username
Password
Remember me

Forgot password?	Register

Username
Password
Remember me

Forgot password?	Register

Iron and Sulfur Isotope Factors of Pyrite: Data from Experimental Mössbauer Spectroscopy and Heat Capacity

Full Text

Abstract

Keywords

About the authors

Supplementary files