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(Fe,Ni)2P allabogdanite can be an ambient pressure phase in iron meteorites.

ABSTRACT: An orthorhombic modification of (Fe,Ni)2P, allabogdanite, found in iron meteorites was considered to be thermodynamically stable at pressures above 8?GPa and temperatures of 1673 K according to the results of recent static high-pressure and high-temperature experiments. A hexagonal polymorphic modification of (Fe,Ni)2P, barringerite, was considered to be stable at ambient conditions. Experimental investigation through the solid-state synthesis supported by ab initio calculations was carried out to clarify the stability fields of (Fe,Ni)2P polymorphs. Both experimental and theoretical studies show that Fe2P-allabogdanite is a low-temperature phase stable at ambient conditions up to a temperature of at least 773?K and, therefore, is not necessarily associated with high pressures. This is consistent with the textural relationships of allabogdanite in iron meteorites.

SUBMITTER: Litasov KD

PROVIDER: S-EPMC7265559 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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(Fe,Ni)2P allabogdanite can be an ambient pressure phase in iron meteorites.

Litasov Konstantin D KD Bekker Tatyana B TB Sagatov Nursultan E NE Gavryushkin Pavel N PN Krinitsyn Pavel G PG Kuper Konstantin E KE

Scientific reports 20200602 1

An orthorhombic modification of (Fe,Ni)2P, allabogdanite, found in iron meteorites was considered to be thermodynamically stable at pressures above 8 GPa and temperatures of 1673 K according to the results of recent static high-pressure and high-temperature experiments. A hexagonal polymorphic modification of (Fe,Ni)2P, barringerite, was considered to be stable at ambient conditions. Experimental investigation through the solid-state synthesis supported by ab initio calcula ...[more]

PMID: 32488079

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(Fe,Ni)2P allabogdanite can be an ambient pressure phase in iron meteorites.

Publications

(Fe,Ni)<sub>2</sub>P allabogdanite can be an ambient pressure phase in iron meteorites.

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