Na-Au intermetallic compounds formed under high pressure at room temperature

Article

关键词: ALKALI-METALS;    TRANSITION;    ALLOYS;    GOLD;    ANNOUNCEMENT;    POTASSIUM;    NATRIUM;    PHASES;    CSAU;   

DOI  :  10.1103/PhysRevB.84.014117

来源: SCIE

【 摘 要 】

High-pressure powder x-ray diffraction experiments have revealed that sodium and gold react at room temperature and form Na-Au intermetallic compounds under high pressure. We have identified four intermetallic phases up to 60 GPa. The first phase (phase I) is the known Na2Au with the tetragonal CuAl2-type structure. It changed to the second phase (phase II) at similar to 0.8 GPa, which has the composition Na3Au with the trigonal Cu3As-type or hexagonal Cu3P-type structure. Phase II further transformed to phase III at 3.6 GPa. Phase III has the same composition, Na3Au, with the cubic BiF3-type structure. Finally, phase III changed to phase IV at similar to 54 GPa. Phase IV gives broad diffraction peaks, indicating large structural disorder.

【 授权许可】

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