Electron. Mater. Lett., Vol. 11, No. 3 (2015), pp. 466-480 Thermoelectric Properties of Metallic Antiperovskites AXD 3 (A=Ge, Sn, Pb, Al, Zn, Ga; X=N, C; D=Ca, Fe, Co) Muhammad Bilal, 1,2 Iftikhar Ahmad, 1,2, * Saeid Jalali Asadabadi, 3 Rashid Ahmad, 4 and Muhammad Maqbool 5 1 Center for Computational Materials Science, University of Malakand, Chakdara 18800, Pakistan 2 Department of Physics, University of Malakand, Chakdara 18800, Pakistan 3 Department of Physics, Faculty of Science, University of Isfahan (UI), Hezar Gerib Avenue, Isfahan 81746-73441, Iran 4 Department of Chemistry, University of Malakand, Chakdara 18800, Pakistan 5 Department of Physics and Astronomy, Ball State University, Muncie, Indiana 47306, USA (received date: 20 November 2014 / accepted date: 28 January 2015 / published date: 10 May 2015) 1. INTRODUCTION Energy is the resource used to exploit all other resources, with increasing demand in recent years because of population growth and industrial development. Over the past decade, there has been a keen interest in exploring efficient thermoelectric (TE) materials for power generation. [1] A sufficiently big quantity of heat is converted into useful energy in TE devices, which makes them a good source of green energy. [2] A key material parameter, related to efficiency is the dimensionless figure of merit, ZT = σS 2 T/k, where σ is the electrical conductivity, S is the Seebeck coefficient, and k = k e + k l is the thermal conductivity, composed of electronic and lattice parts. [3] Materials with ZT above unity are considered excellent candidates for TE applications. [4,5] TE generators have no moving parts so there is complete absence of friction in TE devices which makes them more environment-friendly. [6] Antiperovskites have the general formula AXB 3 , where A is a main group (III-V) element, X is carbon or nitrogen, and B is a transition (s-d) metal. [7,8] These materials usually crystallize in space group Pm3m (221) where the A atom is located at (0, 0, 0), the X atom at (1/2, 1/2, 1/2) and B atom at (0, 1/2, 1/2). [9] Different research groups have investigated thermoelectric properties of various crystal structures like In this paper we communicate the thermoelectric properties of carbon and nitrogen based metallic antiperovskites ANCa (A=Ge, Sn, Pb), BCFe (B=Al, Zn, Ga) and SnCD (D=Co and Fe) using the ab-initio calculations to explore efficient metallic thermoelectric materials. The consistency of the calculated results of SnCCo and SnCFe with the experimental results confirms the reliability of our theoretical calculations for the other investigated metallic antiperovskites. The results indicate that the thermopower of these materials can be enhanced by changing the chemical potential. The dimensionless figure of merit for the three nitrides approaches 0.96 at room temperature, which proves the usefulness of these materials in thermoelectric generators. Furthermore, the thermal conductivity is minimum at room temperature for chemical potential values between -0.25 μ(eV) and 0.25 μ(eV), and provides the maximum values of dimensionless figure of merit in this range. The striking feature of these studies is identifying a metallic compound, SnNCa , with the highest value of Seebeck coefficient at room temperature out of all metals. The results anticipate that these materials could be efficient in thermoelectric generators; however, this needs experimental verification. Keywords: thermoelectric properties, metallic antiperovskites, electrical conductivity, ab-initio calculations, spin orbit coupling DOI: 10.1007/s13391-015-4425-2 *Corresponding author: ahma5532@gmail.com ©KIM and Springer