Effect of anomalous compressibility on Fe diffusion in ferropericlase throughout the spin crossover in the lower mantle

► A complete model of Fe diffusion in the lower mantle ferropericlase is presented. ► The model includes effects of Fe's spin and the associated anomalous compressibility. ► Anomalous compressibility: a cooperative effect for significant Fe concentration. ► Anomalous compressibility increases Fe diffusion in ferropericlase significantly.