Insight into the exemplary structural, elastic, electronic and optical nature of GaBeCl 3 and InBeCl 3 : a DFT study.

In the scheme of density functional theory (DFT), Structural, elastic, electronic, and optical properties calculations of GaBeCl 3 and InBeCl 3 are carried out using Tran-Blaha modified Becke-Johnson exchange potential approximation (TB-mBJ) installed in Wein2k software. Structurally the compounds of interest are found to be stable. Both compounds possess elastic stability, anisotropy, and ductility determined by the elastic studies. The electronic-band structure analysis shows the semiconductor nature of GaBeCl 3 and InBeCl 3 compounds with indirect band gaps of ∼3.08 eV for GaBeCl 3 and ∼2.04 eV for InBeCl 3 along with the symmetrical points from ( X - Γ ). The calculated total density of states (TDOS) and partial density of states (PDOS) of these compounds reveal that for the GaBeCl 3 compound, the contribution of Ga (4p) and Cl (3p) orbital states in the valence, as well as the conduction band, is dominant. While for InBeCl 3 , the contribution of Cl (3p) states as well as In (5s) is large in the valence band and in that of Cl (3p-states) states in the conduction band. The type of chemical bonding is found to be ionic in both compounds. The optical properties i.e. , the real ( ε 1 ( ω )) and imaginary ( ε 2 ( ω )) parts of dielectric function, refractive index n ( ω ), optical reflectivity R ( ω ), optical conductivity σ ( ω ), absorption coefficient α ( ω ), energy loss L ( ω ) and electron extinction coefficient k ( ω ) are also discussed in terms of optical spectra. It is reported that n ( ω ) and k ( ω ) exhibit the same characteristics as ε 1 ( ω ) and ε 2 ( ω ) respectively. Efficient application of these materials can be seen in semiconducting industries and many modern electronic devices.