Francisco Evelio, Pendás Ángel Martín, Suárez Dimas
Departamento Química Física y Analítica, Universidad de Oviedo, Oviedo, Spain.
J Comput Chem. 2025 Jul 30;46(20):e70188. doi: 10.1002/jcc.70188.
This work presents a robust and efficient algorithm for exhaustively determining the critical points (CPs) of the molecular electrostatic potential (MEP) in 3D space. By combining Newton's method with a systematic physical space sampling strategy, we locate all CPs (maxima, minima, and saddle points) for both exact quantum-chemical MEPs and their tricubic interpolated approximations. The method is validated using a test function with known CPs and applied to a diverse set of molecules, including neutral systems, ions, and noncovalent complexes from the S66 and IONIC-HB datasets. Our results demonstrate that the interpolated MEP faithfully reproduces the topology of the exact potential in most cases, with minor discrepancies arising near nuclear positions or in regions of low gradient. The algorithm's efficiency (2-7 faster for interpolated calculations) and robustness make it suitable for large-scale analyses of MEP topologies, offering insights into chemical reactivity and noncovalent interactions.
这项工作提出了一种强大且高效的算法，用于在三维空间中详尽地确定分子静电势（MEP）的临界点（CPs）。通过将牛顿法与系统的物理空间采样策略相结合，我们定位了精确量子化学MEP及其三次立方插值近似的所有CPs（最大值、最小值和鞍点）。该方法通过使用具有已知CPs的测试函数进行了验证，并应用于各种分子，包括中性体系、离子以及来自S66和IONIC - HB数据集的非共价复合物。我们的结果表明，在大多数情况下，插值MEP忠实地再现了精确势的拓扑结构，仅在核位置附近或低梯度区域出现微小差异。该算法的效率（插值计算快2 - 7倍）和稳健性使其适用于MEP拓扑结构的大规模分析，为化学反应性和非共价相互作用提供了见解。
