Thermoelectric property of a new silicon crystal

We present ab initio calculations on thermoelectric properties of a recently synthesised allotrope of silicon crystal [1]. A new silicon crystal with 24 Si atoms per unit cell has open channels along the specific crystallographic direction and shows a quasidirect energy gap of 1.3 eV. Using various first-principles calculation techniques for electrical and thermal conductivity as well as Seebeck coefficient, we find large suppression of thermal conductivity and relatively large Seebeck coefficient in the new silicon crystal, thus demonstrating a competitive thermoelectric figure of merit. \vphantom{.} \noindent [1] D. Y. Kim et al, Nat. Mat. 14, 169 (2015).