Understanding the doping behavior of impurity ions in clinker phases is crucial for controlling the doping effect on clinker compounds, which, however, has not yet been fully demonstrated due to the composition complexity. Herein, we employ the state‐of‐the‐art ab initio calculation to uncover the substitution mechanism of Cu ions in 4 dominant clinker crystals. The defect formation energies indicate Cu ions energetically prefer to substitute Fe ions in ferrite, which is in accord with the experiments. The bond order difference is innovatively postulated to interpret the energy barriers of Cu substitution in comparison with the ionic radius criterion. The high potential barriers of Cu substituting Ca, Si, and Al ions are ascribed to their bond order mismatch, while the tendency of Cu replacing Fe is due to their bond order similarity. Namely, the Cu doping in clinker phases follows the “bond order conformity” principle. In‐depth electronic structure analysis reveals that the bond order is more effective than the ionic radius to estimate potential barriers of Cu substitution in complex clinker system mainly because the latter underestimates the influence of electronic structure differences while the bond order directly measures the bonding structure related to interatomic charge transfer.

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控制复杂熟料系统中铜掺杂行为的基本原理

了解熟料相中杂质离子的掺杂行为对于控制对熟料化合物的掺杂作用至关重要，但是由于组成复杂性，这一点尚未得到充分证明。在此，我们采用最新的从头算技术来发现4种主要熟料晶体中Cu离子的取代机理。缺陷形成能表明，铜离子在铁氧体中更倾向于替代铁离子，这与实验相符。创新地假定键序差与离子半径标准相比可以解释Cu取代的能垒。Cu取代Ca，Si和Al离子的高位势垒归因于它们的键序不匹配，而Cu替代Fe的趋势则归因于它们的键序相似性。即 熟料阶段的铜掺杂遵循“键序一致性”原则。深入的电子结构分析表明，键合顺序比离子半径更有效地估计复杂熟料系统中铜取代的潜在障碍，主要是因为后者低估了电子结构差异的影响，而键合顺序直接测量了相关的键合结构原子间电荷转移。