Two-dimensional Janus transition metal dichalcogenides structures have drawn increasing importance due to their remarkable properties for versatile applications in optoelectronic, photo-catalytic, thermo-electricity, piezoelectricity and spintronic. In this Paper, by employing the Ab-initio computations based on the density functional theory, the structural, electronic and optical properties of Janus MXO (M = Ti, Hf and Zr; X = S and Se) mono-layers are investigated utilizing full potential linearized augmented plane waves (FP-LAPW) method. The lattice parameters of the six Janus were computed, which are close to the previous theoretical results. The density of states and the electronic band structures were investigated for the first time using (GGA-PBE) approximation for the potential of the exchange and correlation. The optical parameters like complex dielectric function, refractive index, reflectivity, extinction and absorption coefficients of all Janus were performed. Our results reveal strong absorption coefficient and low reflectivity in the visible and ultraviolet regions, which make them candidates for opto-electronic and photovoltaic applications.

二维Janus过渡金属二卤化物结构因其在光电，光催化，热电，压电和自旋电子学中的广泛应用而具有非凡的性能，因此日益受到重视。本文通过基于密度泛函理论的Ab-initio计算，对Janus MXO（M = Ti，Hf和Zr； X = S和Se）单层的结构，电子和光学性质进行了全面研究。潜在的线性化增强平面波（FP-LAPW）方法。计算了六个Janus的晶格参数，与先前的理论结果相近。首次使用（GGA-PBE）近似法研究了交换和相关势的态密度和电子能带结构。进行了所有Janus的光学参数，如复介电函数，折射率，反射率，消光系数和吸收系数。我们的结果表明在可见光和紫外线区域具有很强的吸收系数和较低的反射率，这使其成为光电和光伏应用的候选对象。