Theoretical investigation of the electronic structure, optical, elastic and thermodynamics properties of a newly binary boron nitride (T-B3N3)

The ultrasoft pseudopotential planewave (UPPW) within density functional theory (DFT) has been used to investigate the electronic structure, optical, elastic and thermodynamics properties of newly binary boron nitride (T-B3N3). The calculated lattice parameters are in good agreement with previous theoretical results and deviated are less than 0.4%. The electronic structure showed that the T-B3N3 is metallic, and the optical spectra exhibit a noticeable anisotropy. The static dielectric constants, optical permittivity constants and the elastic properties are calculated. From our results, we observe that T-B3N3 is mechanically unstable and ductile. The entropy, enthalpy, free energy, heat capacity and Debye temperature of T-B3N3 was obtained. Up to now, there are no available experimental data about those properties. The results obtained in the present paper could provide important reference data for future studies.