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Re-examining the crystal structure behaviour of nitrogen and methane.

ABSTRACT: In the light of NASA's New Horizons mission, the solid-phase behaviour of methane and nitrogen has been re-examined and the thermal expansion coefficients of both materials have been determined over their whole solid temperature range for the first time. Neutron diffraction results indicate that the symmetric Pa 3 space group is the best description for the ?-nitrogen structure, rather than the long-accepted P213. Furthermore, it is also observed that ?-nitrogen and methane phase I show changes in texture on warming, indicating grain growth.

SUBMITTER: Maynard-Casely HE

PROVIDER: S-EPMC7467175 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Re-examining the crystal structure behaviour of nitrogen and methane.

Maynard-Casely Helen E HE Hester James R JR Brand Helen E A HEA

IUCrJ 20200729 Pt 5

In the light of NASA's New Horizons mission, the solid-phase behaviour of methane and nitrogen has been re-examined and the thermal expansion coefficients of both materials have been determined over their whole solid temperature range for the first time. Neutron diffraction results indicate that the symmetric Pa 3 space group is the best description for the α-nitrogen structure, rather than the long-accepted P213. Furthermore, it is also observed that β-nitrogen a ...[more]

PMID: 32939276

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