[S-IT22] Innovation through the Integration of Solid Earth Science and Materials Science

[SIT22-P03] Bonding properties of liquid Fe-Light-Element-O systems under high pressure: ab initio molecular-dynamics simulations

*Satoshi Ohmura¹, Taku Tsuchiya² (1.Hiroshima Institute of Technology, 2.Ehime University)

Keywords:Liquid Fe alloys, First principles calculations, Bonding properties

Light elements (LE) such as hydrogen, carbon, oxygen, silicon, and sulfur are expected to exist in the Earth's core. For the liquid Fe-LE ternary systems which include two kinds of LE, several experimental and theoretical studies on the immiscibility of liquid Fe–Si–O [1-2] and Fe–S–O [3-4] ternary mixtures under high pressure have been reported. However, it is unclear the bonding properties of liquid Fe–LE–oxide ternary systems, which are the origins of various properties of liquids. For this reason, we have investigated the bonding properties of liquid iron-light-element-oxygen ternary systems such as Fe–H–O, Fe–C–O, Fe–Si–O, and Fe–S–O under high pressure by ab initio molecular dynamics simulations. Regarding the interactions between light elements, bond-overlap populations show covalent characters in C–C, Si–Si, and Si–O interactions in liquid Fe–C–O and Fe–Si–O even under high-pressure condition.


[1] Arveson, S.M., Deng, J., Karki, B.B., and Lee, K.K.M. (2019). Proceedings of the National Academy of Sciences 116, 10238.
[2] Huang, D., Badro, J., Brodholt, J., and Li, Y. (2019). Geophysical Research Letters 46, 6397-6405.
[3] Tsuno, K., Ohtani, E., and Terasaki, H. (2007). Physics of the Earth and Planetary Interiors 160, 75-85.
[4] Helffrich, G., and Kaneshima, S. (2004). Science 306, 2239-2242.