Scipioni, R;
Stixrude, L;
Desjarlais, MP;
(2017)
Electrical conductivity of SiO2 at extreme conditions and planetary dynamos.
Proceedings of the National Academy of Sciences of the United States of America
, 114
(34)
pp. 9009-9013.
10.1073/pnas.1704762114.
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Abstract
Ab intio molecular dynamics simulations show that the electrical conductivity of liquid SiO2 is semimetallic at the conditions of the deep molten mantle of early Earth and super-Earths, raising the possibility of silicate dynamos in these bodies. Whereas the electrical conductivity increases uniformly with increasing temperature, it depends nonmonotonically on compression. At very high pressure, the electrical conductivity decreases on compression, opposite to the behavior of many materials. We show that this behavior is caused by a novel compression mechanism: the development of broken charge ordering, and its influence on the electronic band gap.
| Type: | Article |
|---|---|
| Title: | Electrical conductivity of SiO2 at extreme conditions and planetary dynamos |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1073/pnas.1704762114 |
| Publisher version: | http://doi.org/10.1073/pnas.1704762114 |
| Language: | English |
| Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | high pressure, Earth’s mantle, density functional theory, silicate liquids, electrical conductivity |
| 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 UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/1573136 |
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