Electronic, Elastic, and Vibrational Properties of ZrBeSi via First Principles

Abstract

ZrBeSi is the prototype of the ZrBeSi‐type of crystals, but its fundamental properties have not been well studied till now. In this work, a systematic study on the electronic, elastic, and vibrational properties of ZrBeSi under zero and high pressures has been performed by first‐principles calculation. Calculated electronic properties indicate that ZrBeSi is metallic dictated mainly by the Zr 4d state. Its metallicity weakens as the pressure increases. Studies reveal that sp2 hybridization exists in the Be atoms and their 2p orbitals accept electrons from the Zr atoms, leading them to have an unusual negative valency. Calculated elastic properties imply that ZrBeSi is mechanically stable but anisotropic up to 175 GPa. It has a bulk modulus of 144.4 (142.5) GPa deduced from the third‐order Birch–Murnaghan equation of state (elastic constants) at 0 GPa. Its elastic moduli and elastic anisotropy increase with the rising pressure. Group theory analysis unveils that there are six infrared‐active and four Raman‐active modes at the Brillouin zone center of ZrBeSi. The vibrational patterns of these modes are presented and discussed. Studies further reveal that the frequencies of these modes increase with the rising pressure.