Pyrite-type FeO₂ and FeO₂H were synthesized at the pressure-temperature conditions relevant to Earth’s deep lower mantle. Through the water-iron reaction, the pyrite-phase is a good candidate to explain the chemical heterogeneities and seismological anomalies at the bottom of the mantle. The solid solution of pyrite-type FeO₂ and FeO₂H, namely the FeO₂Hx (0≤x≤1), is particularly interesting and introduces puzzling chemical states for both the O and H atoms in the deep mantle. While the role of H in the FeO₂-FeO₂H system has been primarily investigated, discrepancies remain. In this work, we summarize recent progress on the pyrite-phase, including FeO₂, FeO₂H, and FeO₂Hx, which is critical for understanding the water cycling, redox equilibria, and compositional heterogenicities in the deep lower mantle.

黄铁矿型的FeO ₂和FeO ₂ H在相关的地球深下地幔的压力-温度条件下进行合成。通过水铁反应，黄铁矿相可以很好地解释地幔底部的化学非均质性和地震异常。黄铁矿型的FeO的固溶体₂和FeO ₂ H，即FeO的₂ ħ X（0≤ X ≤1），是特别令人感兴趣的，并引入令人费解的化学状态为在深地幔O和H原子两者。而H在FeO ₂ -FeO _{2中的作用}对H系统进行了初步调查，仍然存在差异。在这项工作中，我们总结了黄铁矿相的最新进展，包括FeO ₂，FeO ₂ H和FeO ₂ H x，这对于理解深部下地幔的水循环，氧化还原平衡和组成异质性至关重要。