Abstract First principles calculations are performed to comparatively reveal the fundamental effects of Ag alloying on phase stability, hydrogen solubility, hydrogen diffusivity, and hydrogen permeability of body-centered-cubic (BCC) and face-centered-cubic (FCC) Pd 8 Cu 8 phases. It is found that the addition of Ag would slightly decrease phase stability of Pd 8 Cu 8 , and the BCC structure of Pd 8 Cu 7 Ag and Pd 7 Cu 8 Ag is energetically more stable than its FCC counterpart at 0 K. Calculations also reveal that crystal structure (BCC or FCC) of PdCuAg and substituting position (Pd or Cu) of Ag should play dominant roles in determining the relative magnitude of hydrogen solubility, hydrogen diffusivity, and hydrogen permeability between PdCuAg and PdCu phases. The present results agree well with experimental observations in the literature, and provide a deep understanding of the fundamental effects of Ag on hydrogen behaviors in PdCu phases.

中文翻译：

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Ag 合金化对 PdCu 中氢行为的基本影响

摘要 通过第一性原理计算，比较揭示了银合金化对体心立方 (BCC) 和面心立方 (FCC) Pd 8 Cu 8 相稳定性、氢溶解度、氢扩散率和氢渗透率的基本影响。阶段。发现加入Ag会略微降低Pd 8 Cu 8 的相稳定性，并且Pd 8 Cu 7 Ag和Pd 7 Cu 8 Ag的BCC结构在0 K时比其FCC对应物在能量上更稳定。计算还显示PdCuAg 的晶体结构（BCC 或 FCC）和 Ag 的取代位置（Pd 或 Cu）应该在决定 PdCuAg 和 PdCu 相之间的氢溶解度、氢扩散率和氢渗透率的相对大小方面起主导作用。目前的结果与文献中的实验观察结果非常吻合，