The molecular mechanism of the reactions between four carbonyl oxides and ammonia/water are investigated using the M06-2X functional together with 6-311++G(d,p) basis set. The analysis of activation and reaction enthalpy shows that the exothermicity of each process increased with the substitution of electron donating substituents (methyl and ethenyl). Along each reaction pathway, two new chemical bonds C−N/C−O and O−H are expected to form. A detailed analysis of the flow of the electron density during their formation have been characterized from the perspective of bonding evolution theory (BET). For all reaction pathways, BET revealed that the process of C−N and O−H bond formation takes place within four structural stability domains (SSD), which can be summarized as follows: the depopulation of V(N) basin with the formation of first C−N bond (appearance of V(C,N) basin), cleavage of N−H bond with the creation of V(N) and V(H) monosynaptic basin, and finally the V(H,O) disynaptic basin related to O−H bond. On the other hand, in the case of water, the cleavage of O−H bond with the formation of V(O) and V(H) basins is the first stage, followed by the formation of the O−H bond as a second stage, and finally the creation of C−O bond.

中文翻译：

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使用键演化理论探索羰基氧化物与氨/水之间化学反应的电子密度序列

使用 M06-2X 泛函和 6-311++G(d,p) 基组研究了四种羰基氧化物与氨/水反应的分子机制。活化和反应焓分析表明，每个过程的放热随着给电子取代基（甲基和乙烯基）的取代而增加。沿着每个反应途径，预计会形成两个新的化学键 C-N/CO-O 和 O-H。从成键演化理论 (BET) 的角度对电子密度在形成过程中的流动进行了详细分析。对于所有反应途径，BET 揭示了 CN 和 O-H 键的形成过程发生在四个结构稳定域 (SSD) 内，可总结如下：随着第一个 C−N 键的形成（V(C,N) 盆的出现），V(N) 盆地的人口减少，随着 V(N) 和 V(H) 单突触盆的产生，N−H 键的断裂，最后是与 O-H 键相关的 V(H,O) 非突触盆地。另一方面，在水的情况下，第一阶段是 O-H 键断裂，形成 V(O) 和 V(H) 盆地，然后形成 O-H 键作为第二阶段阶段，最后是创建 CO 键。