Ni as an alloying addition in Zircaloy leads to an increase in hydrogen pick-up fraction. Atomic scale simulations of tetragonal ZrO₂, based on density functional theory, are used to identify a possible mechanism for this observation. First, defect formation energies associated with Ni but also Fe and Cr are used to predict relative defect cluster and defect charge concentrations using Brouwer diagrams. At low oxygen partial pressures ($P_{{\text{O}}_2}$), expected in the vicinity of the oxide metal interface, a cluster consisting of an oxygen vacancy adjacent to a charge neutral Ni⁰ atom is identified as the most populous cluster. Further simulations show that a hydrogen molecule will dissociate in the vicinity of this cluster. No other cluster is both sufficiently populous and acts in this way. This differentiates Ni from the other alloying elements.

锆作为锆合金中的合金添加物会导致氢吸收分数的增加。基于密度泛函理论的四方ZrO ₂原子尺度模拟被用来识别这种观察的可能机制。首先，与镍相关的缺陷形成能量，以及与铁和铬相关的缺陷，都使用布劳维尔图来预测相对的缺陷簇和缺陷电荷浓度。在低氧分压下（$P_{{\text{Ø}}_{\mathrm{2个}}}$），预期在氧化物金属界面附近，由与电荷中性Ni ⁰原子相邻的氧空位组成的簇被认为是人口最多的簇。进一步的模拟表明，氢分子将在该簇附近解离。没有其他集群既有足够的人口，又有这种举动。这将Ni与其他合金元素区分开来。