First-order isostructural Mott transition in highly compressed MnO.
We present evidence for an isostructural, first-order Mott transition in MnO at 105+/-5 GPa, based on high-resolution x-ray emission spectroscopy and angle-resolved x-ray diffraction data. The pressure-induced structural and spectral changes provide a coherent picture of MnO phase transitions from paramagnetic B1 to antiferromagnetic distorted B1 at 30 GPa, to paramagnetic B8 at 90 GPa, and to diamagnetic B8 at 105+/-5 GPa. The last is the Mott transition, accompanied by a significant loss of magnetic moment, an approximately 6.6% volume collapse and the insulator-metal transition as demonstrated by recent resistance measurements.
Yoo
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CS
Lawrence Livermore National Laboratory, Livermore, CA 94551, USA.
Maddox
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B
Klepeis
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JH
Iota
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Evans
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W
McMahan
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A
Hu
M Y
MY
Chow
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Somayazulu
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Häusermann
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Scalettar
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Pickett
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