Electrical resistivity and thermal conductivity of Iron-Hydrogen Alloys at Earth's Core Conditions

The electrical and thermal conductivity of iron are of great significance in the stability and evolution of planetary magnetic fields. However, the thermal transport properties of iron alloys (doped with light elements) at high pressure (P) and temperature (T) conditions remain uncertain. Here we investigated the thermal transport properties of the hexagonal close packed (hcp) Fe doped with varying H content at Earth’s core conditions, corresponding to pressures of about 130 and 300 GPa and temperatures of 4000 and 6000 K. Starting from molecular dynamic simulations, we verified that Fe-H alloys maintain superionic phase at Earth’s core conditions, where H diffuse freely in solid Fe framework. Utilizing the KKR method within density functional theory (DFT) plus Dynamical mean-field Theory (DMFT), we found a linear increase in electrical resistivity and a linear decrease in thermal conductivity as the hydrogen content increased, all while keeping the iron density constant.<!-- notionvc: 1f341a9d-fa72-4228-b07b-8b67177d6a0a -->