Thermoelectric, structural, electronic, magnetic, and thermodynamic properties of CaZn2Ge2 compound

The structural, electronic, magnetic, thermoelectric and thermodynamic properties of CaZn2Ge2 compound from zintl family was examined under the frame work of density functional theory (DFT). The optimization results indicated that the Ferromagnetic configuration is the stable one. From the band structure and electrical conductivity (sigma/tau) calculations CaZn2Ge2 reveled metallic nature. The strong hybridization was observed between Ca-d and Ge-p states, whereas as a whole it showed mix ionic and covalent bonding nature. The reported low magnetic moments of the compound by and (GGA + U) approximations revealed weak ferromagnetism. Due to these unique properties, the material is promising for spintronics devices and magnetic applications. Furthermore for the calculation of thermoelctric properties the Boltztrap code was used in the temperature range from 0 to 1000 K. The maximum electrical conductivity (sigma/tau) and negative seebeck coefficient (S) with the values 5.6 X10(20)(Omega.m.s)(-1) and - 2.25X10(-5) mu V/K were reached below the room temerature while maximum ZT with a value 0.0171 and power factor were achieved at 1000 K. This finding increased the demand of use this material in waste heat management. Moreover, the thermodynamic properties for CaZn2Ge2 compound in the pressure range from 0 to 18GPa and temperature variation from 200 to 1400 K were discussed.