First-Principles Study of the Binary Intermetallics in the Cu-Lu and Cu-Pm Systems

First-Principles Study of the Binary Intermetallics in the Cu-Lu and Cu-Pm Systems

Nawel Djenane Yassine DjaballahAissa Belgacem-Bouzida Mourad Guezlane 

Laboratory of Physical and Chemical of Materials (LEPCM), Physics Department, Faculty of Matter Science, University of Batna 1, Algeria

Corresponding Author Email:
31 December 2017
25 June 2018
31 December 2018
| Citation



We present a first principle study of the structural, elastic and energetic properties of the CuaXb (X=Lu, Pm) compounds, within the first principles density functional theory (DFT). The equilibrium volume, lattice constant, enthalpy of formation and the elastic constant are calculated using the full-potential linearized augmented plane-wave [FP-LAPW] method in the generalized gradient approximation (GGA) scheme. The CuLu, Cu2Lu, Cu5Lu, CuPm, Cu2Pm, Cu4Pm, Cu5Pm and Cu6Pm were investigated in their similar Cu-Lanthanide structure prototype compounds observed experimentally. The Cu7Lu2, Cu9Lu2 and Cu7Pm2 intermetallics reported without prototype structure, was also investigated by inspecting several hypothetical structures. The most stable structure for the Cu7X2 compounds was found to be the orthorhombic structure in the Ag7Yb2 prototype. For the Cu9Lu2 compound the two structures studied have a positive enthalpy, implying that it is not a ground state for both tested.


Cu-Lu compounds, Cu-Pm compounds, First principles calculations, Rare earth alloys

1. Introduction
2. Computational Details
3. Results and Discussion
4. Conclusions

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