This study aims to delve into the exploration of stable bulk phases of AgAu by employing a synergistic combination of evolutionary algorithms and density functional theory. Through our comprehensive investigations, we uncover the existence of stable phases, specifically the cubic $\mathit{Pm}\overline{3}m$ and trigonal $R\overline{3}m$ crystals, which exhibit remarkable mechanical and dynamic stabilities. Our study reveals the presence of metastable hexagonal (P6₃/mmc, P $\overline{6}$ m2) and tetragonal (P4₂/mmm) structures within the AgAu system, expanding our understanding of its phase behavior. The calculations demonstrate that the dominant negative contribution on the overall formation energy arises from the chemical energy arising through AgAu charge exchange. As a consequence, this chemical effect plays a pivotal role in promoting strong bonding interactions and significantly enhances the thermodynamic stability of AgAu alloys.

Furthermore, we conduct an extensive analysis of the plasmonic and optical properties manifested by these stable phases. Our findings unequivocally demonstrate the manifestation of plasmon resonances in the visible-violet and visible-blue regions for cubic Ag₃Au and AgAu₃ crystals, respectively. Notably, the trigonal-AgAu phase exhibits a robust excitation of plasmons exclusively within the visible-blue spectral domain. Moreover, Ag₃Au, AgAu, and AgAu₃ show strong absorption behavior in the near-infrared and ultraviolet-C spectral regions. Additionally, Ag₃Au exhibits a pronounced reflectivity behavior within the near-infrared (IR) and ultraviolet-B spectral regions. AgAu, on the other hand, displays strong reflectance within the visible-violet spectral region. Finally, AgAu₃ manifests a notable reflection within the visible-blue electromagnetic spectral region.

本研究旨在通过采用进化算法和密度泛函理论的协同组合，深入探索 Ag Au 的稳定体相。通过我们的全面研究，我们发现了稳定相的存在，特别是立方相$\mathit{下午}\stackrel{￣}{3}米$和三角形$右\stackrel{￣}{3}米$晶体，表现出卓越的机械和动态稳定性。我们的研究揭示了亚稳态六方晶系 ( P 6 ₃ /mmc, P $\stackrel{￣}{6}$m2) 和Ag Au 系统中的四方 ( P 4 ₂ /mmm) 结构，扩展了我们对其相行为的理解。计算表明，对总体形成能的主要负贡献来自于 Ag Au 电荷交换产生的化学能。因此，这种化学效应在促进强键合相互作用方面发挥着关键作用，并显着增强了 AgAu 合金的热力学稳定性。

此外，我们对这些稳定相表现出的等离子体和光学特性进行了广泛的分析。_{我们的研究结果明确证明了立方 Ag 3} Au 和 AgAu _3晶体的等离激元共振分别在可见紫光和可见蓝色区域中的表现。值得注意的是，三角银金相仅在可见蓝色光谱域内表现出强烈的等离激元激发。此外，Ag ₃ Au、AgAu和AgAu ₃在近红外和紫外C光谱区表现出强吸收行为。此外，Ag ₃ Au 在近红外 (IR) 和紫外-B 光谱区域内表现出明显的反射行为。另一方面，AgAu 在可见紫光谱区域表现出很强的反射率。最后，AgAu ₃在可见蓝色电磁光谱区域内表现出显着的反射。