- Award ID(s):
- 1946231
- NSF-PAR ID:
- 10319528
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry A
- Volume:
- 125
- Issue:
- 36
- ISSN:
- 1089-5639
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Iron nitrides are possible constituents of the cores of Earth and other terrestrial planets. Pressure‐induced magnetic changes in iron nitrides and effects on compressibility remain poorly understood. Here we report synchrotron X‐ray emission spectroscopy (XES) and X‐ray diffraction (XRD) results for ε‐Fe7N3and γ′‐Fe4N up to 60 GPa at 300 K. The XES spectra reveal completion of high‐ to low‐spin transition in ε‐Fe7N3and γ′‐Fe4N at 43 and 34 GPa, respectively. The completion of the spin transition induces stiffening in bulk modulus of ε‐Fe7N3by 22% at ~40 GPa, but has no resolvable effect on the compression behavior of γ′‐Fe4N. Fitting pressure‐volume data to the Birch‐Murnaghan equation of state yields
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Abstract The Ag and In co‐doped PbTe, Ag
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