Li, Y;
Wang, Y;
Pickard, CJ;
Needs, RJ;
Wang, Y;
Ma, Y;
(2015)
Metallic icosahedron phase of sodium at terapascal pressures.
Physical Review Letters
, 114
(12)
, Article 125501. 10.1103/PhysRevLett.114.125501.
Preview |
Text
Li_Metallic icosahedron phase of sodium at terapascal pressures.pdf Download (1MB) | Preview |
Abstract
Alkali metals exhibit unexpected structures and electronic behavior at high pressures. Compression of metallic sodium (Na) to 200 GPa leads to the stability of a wide-band-gap insulator with the double hexagonal hP4 structure. Post-hP4 structures remain unexplored, but they are important for addressing the question of the pressure at which Na reverts to a metal. Here, we report the reentrant metallicity of Na at the very high pressure of 15.5 terapascal (TPa), predicted using first-principles structure searching simulations. Na is therefore insulating over the large pressure range of 0.2-15.5 TPa. Unusually, Na adopts an oP8 structure at pressures of 117-125 GPa and the same oP8 structure at 1.75-15.5 TPa. The metallization of Na occurs on the formation of a stable and striking body-centered cubic cI24 electride structure consisting of Na_{12} icosahedra, each housing at its center about one electron that is not associated with any Na ions.
| Type: | Article |
|---|---|
| Title: | Metallic icosahedron phase of sodium at terapascal pressures |
| Location: | United States |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1103/PhysRevLett.114.125501 |
| Publisher version: | http://dx.doi.org/10.1103/PhysRevLett.114.125501 |
| Language: | English |
| Additional information: | © 2015 American Physical Society |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences |
| URI: | https://discovery.ucl.ac.uk/id/eprint/1468860 |
Loading...
Loading...Loading...| 1. |  United States | 9 |
| 2. |  China | 3 |
| 3. |  Russian Federation | 1 |
| 4. |  Vietnam | 1 |
Archive Staff Only
 |
View Item |
