Electronic Properties of the ChalcopyritesAgFeS2, AgFeSe2 and AgFeTe2 Compounds

The electronic properties of the ChalcopyritesAgFeS₂, AgFeSe₂ and AgFeTe₂ have been investigated using the pseudopotential method within the density functional theory (DFT). The LDA+U technique and the projector augmented waves (PAW) were used for the electronic band structure calculations, while the norm-conserving pseudopotentials were used for the structure optimization. The calculated results showed that AgFeS₂, AgFeSe₂ and AgFeTe₂ are semiconductors with energy bandgap values of 3.33 eV, 0.05 eV and 1.30 eV respectively. The transition points in the band structure were all notable because of the narrowness of the bands about the Fermi level. The total density of states and their corresponding partial density of states were also computed.