First-principles study on physical properties of actinide-based ternary (UC)mAl3C2 (m = 1, 2, 3) carbides

Abstract

Physical properties of (UC)mAl3C2 (m = 1, 2, 3) carbides are calculated using Wien2k simulation code and results are presented in this paper. Ternary UAl3C3, U2Al3C4 and U3Al3C5 carbides are mechanically and thermodynamically stable. The dynamical stability of (UC)mAl3C2 has been confirmed by phonon calculations. The calculated formation energies of UAl3C3, U2Al3C4 and U3Al3C5 carbides are found to be negative validating their structural stability. Calculated mechanical properties shows the ductile behavior of U3Al3C5 carbide, while UAl3C3 and U2Al3C4 carbides are brittle in nature. Mechanical anisotropy results reveal that the U3Al3C5 has greatest anisotropy characteristics. Calculated electronic and dielectric properties confirm the conducting nature of all these carbides. All three carbides show the highest reflectivity in infrared and ultraviolet regions. In the visible region, the observed average reflectivity is about 40–50%, which suggests that these carbides have ability to reduce solar radiation. Thermodynamic properties are also calculated at different pressures and results are discussed. Debye temperature is also investigated to explore the vibrational response of studied carbides. Thermoelectric properties are also calculated using boltztrap2 code. Mechanical, Optical, thermodynamic and thermoelectric properties suggest that these carbides could be suitable candidates for electronic, optical, energy storage devices and thermal barrier coating (TBCs) materials.