AI 中文总结
该研究对比了基于稀有气体配位的几何电负性表与其他模型在52个分子/离子上的电荷预测，发现其存在极性反转等结构问题，按周期解析电负性尺度可修正这些问题。
AI 中文摘要
电荷均衡模型预测分子内电子的重新分布，其计算成本低于量子化学方法，且每个模型都以原子电负性和硬度表为基础。近期有一个电负性和硬度表，用一个几何量替代了电离能和电子亲和能：即每个主族原子到其所在周期稀有气体的分数距离。在保持几何结构、静电阻尼和分子列表固定的前提下，我们在B3LYP/def2-TZVP级别对52个分子和离子组成的主要数据集，将该表与光谱值、其自身拟合的核函数以及二次对照模型进行了比较。该表的结构而非均衡求解器会产生两个结构后果：处于相等分数距离的原子会获得相同的电负性，因此一氯化氟、一溴化碘和二氧化硫的偶极矩会完全消失，且会丢失测量到的HF/HCl的0.72德拜偶极矩差值；由于第一周期被排除，氢的光谱电负性高于所有几何值，这反转了O-H、N-H及氢-卤键的极性。在相同拟合条件下，几何核函数与二次核函数的原子电荷偏差为0.0022电子，因此预测结果由拟合的能量尺度而非核函数形状决定。按周期解析电负性尺度可恢复所有5个多原子重原子-氢测试中的正确极性。
英文摘要
Charge-equilibration models predict how electrons redistribute over a molecule more cheaply than quantum chemistry, and each begins from a table of atomic electronegativities and hardnesses. A recent table replaces ionization energies and electron affinities with one geometric quantity: each main-group atom's fractional distance to the noble gas closing its row. Holding geometries, electrostatic damping and the molecule list fixed, we compare it with spectroscopic values, with its own kernel refitted, and with a quadratic control, over a primary set of fifty-two molecules and ions at the B3LYP/def2-TZVP level. Two structural consequences follow from the table construction rather than the equalization solver. Atoms at equal fractional distance receive identical electronegativities, so the dipole moments of chlorine monofluoride, iodine monobromide and sulfur dioxide vanish exactly, and the measured $0.72$ debye $\mathrm{HF}/\mathrm{HCl}$ gap is lost. Because the first period is excluded, hydrogen retains its spectroscopic electronegativity above every geometric value, reversing $\mathrm{O{-}H}$, $\mathrm{N{-}H}$ and hydrogen-halide polarity. Fitted alike, geometric and quadratic kernels agree to $0.0022$ electron per atom, so predictions are set by the fitted energy scales, not the kernel shape. Resolving the electronegativity scale period by period restores correct polarity in all five polyatomic heavy-atom-hydrogen tests.
Comments46 pages, 9 figures, 9 tables. Supporting Information and data/code archive included as ancillary files
