The electronic structure and optical properties of AgIn_1−xGa_xY₂ (Y = Se, Te) are investigated using first-principles calculations based on density functional theory. Both the local density approximation (LDA) and generalized gradient approximation (GGA) are employed in the calculation. The crystal structure of ternary semiconductors is the tetragonal chalcopyrite structure with space group \({\text{I}}\overline{{4}} {\text{2d}}\). The lattice parameters a(Å) and c(Å) are found to vary with the change in Ga composition. The energy gap across the Fermi level in the density of states plots shows that these materials are semiconductors. To compute accurate energy gap values, the LDA + U method is adopted. The calculated elastic constants indicate that these compounds are mechanically stable at normal pressure. The semiconducting nature of these materials may prove their applications in solar cells and photovoltaic absorbers. The optical parameters such as dielectric function, electron energy loss function, refractive index and reflectivity are computed.

利用基于密度泛函理论的第一性原理研究了AgIn _{1- x} Ga _x Y ₂（Y = Se，Te）的电子结构和光学性质。计算中采用了局部密度近似（LDA）和广义梯度近似（GGA）。三元半导体的晶体结构是空间空间为\（{\ text {I}} \ overline {{4}} {\ text {2d}} \）的四方黄铜矿结构。。发现晶格参数a（Å）和c（Å）随Ga组成的变化而变化。在状态密度图中费米能级上的能隙表明这些材料是半导体。为了计算准确的能隙值，采用了LDA + U方法。计算出的弹性常数表明这些化合物在常压下机械稳定。这些材料的半导体性质可以证明其在太阳能电池和光伏吸收器中的应用。计算诸如介电函数，电子能量损失函数，折射率和反射率的光学参数。