Local structure of molten AuGa<sub>2</sub> under pressure [electronic resource] : Evidence for coordination change and planetary implications
- Washington, D.C. : United States. National Nuclear Security Administration, 2018.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- Article numbers 6,844 : digital, PDF file
- Additional Creators:
- University of California, Berkeley
United States. National Nuclear Security Administration
United States. Department of Energy. Office of Scientific and Technical Information
- In situ x-ray diffraction measurements and inverse Monte Carlo simulations of pair distribution functions were used to characterize the local structure of molten AuGa<sub>2</sub> up to 16 GPa and 940 K. Our results document systematic changes in liquid structure due to a combination of bond compression and coordination increase. Empirical potential structure refinement shows the first-neighbor coordination of Ga around Au and of Au around Ga to increase from about 8 to 10 and 4 to 5, respectively between 0 and 16 GPa, and the inferred changes in liquid structure can explain the observed melting-point depression of AuGa2 up to 5 GPa. As intermetallic AuGa<sub>2</sub> is an analogue for metallic SiO<sub>2</sub> at much higher pressures, our results imply that structural changes documented for non-metallic silicate melts below 100 GPa are followed by additional coordination changes in the metallic state at pressures in the 0.2–1 TPa range achieved inside large planets.
- Published through SciTech Connect.
Scientific Reports 8 1 ISSN 2045-2322 AM
Bora Kalkan; Budhiram Godwal; Selva Vennila Raju; Raymond Jeanloz.
- Funding Information:
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