The structure and electronic properties of hexagonal Fe₂Si

On the basis of first principle calculations, we show that a hexagonal structure of Fe₂Si is a ferromagnetic crystal. The result of the phonon spectra indicates that it is a stable structure. Such material exhibits a spin-polarized and half-metal-like band structure. From the calculations of generalized gradient approximation, metallic and semiconducting behaviors are observed with a direct and nearly 0 eV band gap in various spin channels. The densities of states in the vicinity of the Fermi level is mainly contributed from the d-electrons of Fe. We calculate the reflection spectrum of Fe₂Si, which has minima at 275 nm and 3300 nm with reflectance of 0.27 and 0.49, respectively. Such results may provide a reference for the search of hexagonal Fe₂Si in experiments. With this band characteristic, the material may be applied in the field of novel spintronics devices.