[19a-436-1~8] 13.2 Exploratory Materials, Physical Properties, Devices

[19a-436-5] On the possibility of Mg₂(Si, C) with the anti-fluorite structure

〇Yoji Imai¹, Atsushi Yamamoto¹, Ken-ichi Takarabe² (1.AIST, 2.Okayama Univ. Sci)

Keywords:Mg2Si, carbon substitution, band gap

In view of the reported results that Mg₂C with the anti-fluorite structure becomes stable under high pressure, we attempted to predict whether the solid solution of Mg₂Si_XC_1-X with the same structure might be stable under high pressures using first-principle calculations. Though it was predicted that Mg₂Si_XC_1-X would be energetically more stable than Mg+ Si + C under higher pressures, it was found that the substitution of Si in the Mg₂Si lattice with C atoms would cause band gap shrinkage in spite of our expectations.