Atom Pair Contribution Method: Fast and General Procedure To Predict Molecular Formation Enthalpies

An atom pair contribution (APC) model aimed at predicting the gas-phase formation enthalpy (ΔfH°) of molecules is reported. In contrast to bond contribution (BC) or group contribution (GC) methods, it relies on increments associated with pairs of bonded and geminal atoms along with 15 structural corrections. Another distinctive feature of the present APC method is the large amount of experimental and high-level theoretical data specially compiled in this work to fit and validate the model (2671 entries). Unlike GC methods, the present APC model has wide applicability with the number of adjustable parameters limited to 68. Although it requires only a structural formula as input and involves only back-of-the-envelope calculations, it is more reliable than state-of-the-art quantitative structure–property relationship methods, popular semiempirical Hamiltonians, and even low-level density functional theory approaches based on gradient-corrected functionals. It is therefore a valuable tool for fast screening applications or whenever chemical accuracy is not necessary.本研究报道了一种用于预测分子气相生成焓（ΔfH°）的原子对贡献（Atom Pair Contribution, APC）模型。与键贡献（Bond Contribution, BC）或基团贡献（Group Contribution, GC）方法不同，该模型依托键合原子与偕原子的成对增量项，并结合15项结构校正项构建。本APC方法的另一显著特征是，本研究专门编译了共计2671条的实验与高精度理论数据，用于模型的拟合与验证。与基团贡献（GC）方法相比，本APC模型可调参数仅为68个，却具备更广泛的适用性。尽管该模型仅需分子结构式作为输入，且仅需简易纸笔估算即可完成计算，但其可靠性优于当前领先的定量构效关系（Quantitative Structure-Property Relationship, QSPR）方法、常用半经验哈密顿方法，乃至基于梯度校正泛函的低阶密度泛函理论方法。因此，本模型可作为快速筛选类应用或无需化学精度场景下的实用工具。