Electrical conductivity of the lower‐mantle ferropericlase across the electronic spin transition

摘要: [1] Electrical conductivity of the lower-mantle ferropericlase-(Mg0.75,Fe0.25)O has been studied using designer diamond anvils to pressures over one megabar and temperatures up 500 K. The electrical (Mg0.75,Fe0.25)O gradually rises by an order magnitude 50 GPa but decreases a factor approximately three between 70 GPa. This decrease in is attributed isosymmetric high-spin low-spin transition iron ferropericlase. That is, electronic spin results mobility and/or density charge transfer carriers activation energy ferropericlase 0.27 eV at 101 GPa, consistent with small polaron conduction (electronic hopping, transfer). Our indicate that exhibits lower than ferropericlase, which needs be considered future geomagnetic models for mantle.