The electronic structures and chemical stability of anosovite M3O5 (M: Mg, Fe, Ti): DFT plus U and ab initio molecular dynamics study

The scarcity of high-grade rutile and utilization difficulty of low-grade titanium slag are two major problems faced by the global titanium industry. The phase of low-grade titanium resources is complex and changeable with the substitution of Ti by Mg and Fe. The presence of impurities in anosovite M3O5 will inevitably change the microstructure of the crystal parameters and electronic structure, and ultimately affect the subsequent carbochlorination process. To our knowledge, the stability of electrons and structures for anosovite M3O5 (M: Mg, Fe, Ti) with different components has not been systematically reported. Based on DFT + U approach, energy band, density of state, electron density difference, and Mulliken populations was calculated to elucidate the stability differences and essential reason of Ti3O5, MgTi2O5, FeTi2O5 and MgTi4FeO10. The results show that the addition of Mg and Fe reduces the stability of M3O5, which is consistent with the ab initio molecular dynamics (AIMD) simulation of carbochlorination process for anosovite.