Existence of spin-polarized Dirac cone in Sc2CrB6: A DFT study

Abstract First principles calculations on Sc 2 CrB 6 crystal revealed the existence of Dirac Cone in its electronic structure for the first time. The compound has an interesting crystal structure with 2D boron layers with hexagonal, pentagonal, heptagonal boron rings sandwiched between the metal layers. Calculations show that the compound has a mixed covalent and metallic nature of the bonding. Also, ground state ferromagnetic behaviour is predicted for the metallic bonded Sc 2 CrB 6 . Here the magnetization arises mostly from the Cr atom with enhanced contribution from the remaining elements. Interestingly, band crossing is seen at the Fermi level with spin polarization indicating the existence of Dirac cone in Sc 2 CrB 6 . Apart from this, high-pressure calculations up to about 67 GPa reveal a pressure-induced transition from ferromagnetic state to non-magnetic state around 30.3 GPa.