The melting curve of iron at the pressures of the Earth's core from ab initio calculations

被引:237
作者
Alfè, D
Gillan, MJ
Price, GD
机构
[1] Univ London Birkbeck Coll, Res Sch Geol & Geophys Sci, London WC1E 6BT, England
[2] Univ London Univ Coll, Dept Phys & Astron, London WC1E 6BT, England
关键词
D O I
10.1038/46758
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
The solid inner core of the Earth and the liquid outer core consist mainly of iron(1) so that knowledge of the high-pressure thermodynamic properties of iron is important for understanding the Earth's deep interior. An accurate knowledge of the melting properties of iron is particularly important, as the temperature distribution in the core is relatively uncertain(2-4) and a reliable estimate of the melting temperature of iron at the pressure of the inner-core boundary would put a much-needed constraint on core temperatures. Here we used ab initio methods to compute the free energies of both solid and liquid iron, and we argue that the resulting theoretical melting curve competes in accuracy with those obtained from high-pressure experiments. Our results give a melting temperature of iron of similar to 6,700 +/- 600 K at the pressure of the inner-core boundary, consistent with some of the experimental measurements. Our entirely ab initio methods should also be applicable to many other materials and problems.
引用
收藏
页码:462 / 464
页数:3
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