Greigite (Fe3S4) is thermodynamically stable: Implications for its terrestrial and planetary occurrence

Tamilarasan Subramani, Kristina Lilova, Mykola Abramchuk, Kurt D. Leinenweber, Alexandra Navrotsky

Research output: Contribution to journalArticlepeer-review

Abstract

Iron sulfide minerals are widespread on Earth and likely in planetary bodies in and beyond our solar system. Using measured enthalpies of formation for three magnetic iron sulfide phases: bulk and nanophase Fe3S4 spinel (greigite), and its high-pressure monoclinic phase, we show that greigite is a stable phase in the Fe–S phase diagram at ambient temperature. The thermodynamic stability and low surface energy of greigite supports the common occurrence of fine-grained Fe3S4 in many anoxic terrestrial settings. The high-pressure monoclinic phase, thermodynamically metastable below about 3 GPa, shows a calculated negative P-T slope for its formation from the spinel. The stability of these three phases suggests their potential existence on Mercury and their magnetism may contribute to its present magnetic field.

Original languageEnglish (US)
Pages (from-to)28645-28648
Number of pages4
JournalProceedings of the National Academy of Sciences of the United States of America
Volume117
Issue number46
DOIs
StatePublished - Nov 17 2020

Keywords

  • Greigite | thermodynamic stability | terrestrial planets | magnetism | high pressure

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Greigite (Fe<sub>3</sub>S<sub>4</sub>) is thermodynamically stable: Implications for its terrestrial and planetary occurrence'. Together they form a unique fingerprint.

Cite this