Fe$_{4}$O$_{5}$: HP-HT synthesis and properties

Recently, a new iron oxide, Fe$_{4}$O$_{5}$ has been synthesized at high-pressure high-temperature (HP-HT) conditions [1,2]. In this work using multi-anvil large-volume cells we investigated the synthesis conditions of Fe$_{4}$O$_{5}$ in wide ranges pressures of 9-24 GPa and temperatures of 900-1800 C. We have prepared both single crystals and bulk polycrystalline samples of Fe$_{4}$O$_{5}$. We investigated the chemical composition and the microstructure of Fe$_{4}$O$_{5}$. From a single-crystal diffraction study we have refined the crystal structure of Fe$_{4}$O$_{5}$. We have studied compressibility of Fe$_{4}$O$_{5}$ up to 50 GPa. In addition, we studied magnetic, optical and electronic transport properties of Fe$_{4}$O$_{5}$ at ambient pressure. These studies included magnetic susceptibility, magnetization, Mossbauer spectroscopy, Raman and Infra-red spectroscopy, electrical resistivity. We have performed also calculations of the lattice stability and electronic band structure of Fe$_{4}$O$_{5}$\\[4pt] [1] B. Lavina, et al., Proc Nat. Acad. Sci. US 108, 17281 (2011).\\[0pt] [2] A. B Woodland, et al., Am. Miner. 97, 1808 (2012).