High-pressure structure of half-metallic CrO2
نویسندگان
چکیده
Evidence for a structural phase transition from rutile -CrO2 phase I P42/mnm to orthorhombic -CrO2 phase II CaCl2-like, Pnnm is presented using angle-resolved synchrotron x-ray diffraction and highsensitivity confocal Raman spectroscopy. The transition to the CaCl2 structure, which appears to be second order, occurs at 12±3 GPa without any measurable discontinuity in volume, but is accompanied by an apparent increase in compressibility. Raman data are also presented to show further evidence for a second-order structural phase transition as well to demonstrate soft-mode behavior of the B1g phonon mode.
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