氢键酸度的量子化学参数表示

研究了137个化合物的总氢键酸度(∑A₂^H)与量子化学参数的相关性.对于含羟基或羧基化合物,∑A₂^H=-0.027⁷⁺3.826Q_H-0.0273E_LUMO-0.0654E_HOMO+3.085Q_O(n=70,r=0.982),其中Q_H表示羟基或羧基氢原子净电荷,E_LUMO表示最低未占据分子轨道能级,E_HOMO表示最高占据分子轨道能级,Q_O表示羟基或羧基中与氢原子连接的氧原子净电荷;对于含氨基化合物,∑A₂^H=-1.569+3.637Q_H-0.1235E_HOMO(n=49,r=0.985),其中Q_H表示氨基中较正氢原子的净电荷;对于含亚氨基化合物,∑A₂^H=-0.472+3.676Q_H(n=18,r=0.993),其中Q_H表示亚氨基氢原子的净电荷.

Describing Hydrogen-Bond Acidity with Quantum Chemical Parameters

The correlations between the overall hydrogen-bond acidities ∑αH2 of 137 diverse compounds and their quantum chemical parameters have been studied. For the compounds having hydroxyl or carboxyl, ∑αH2=－0.027 7＋3.826QH－0.027 3ELUMO－0.065 4EHOMO＋3.085QO（n =70, r=0.982 ）. The quantum chemical parameters QH, ELUMO, EHOMO and QO are the net charge of the hydrogen atom in the hydroxyl or carboxyl of the compounds, the energy of the lowest unoccupied molecular orbital, the energy of the highest occupied molecular orbital and the net charge of the oxygen binding with the hydrogen atom in the hydroxyl or carboxyl, respectively. For the compounds having amino group, ∑αH2=－1.569＋3.637QH－0.123 5EHOMO(n=49, r=0.985). QH is the net charge of the hydrogen atom having greater positive net charge in the amino group. For the compounds having imino group, ∑αH2=－0472＋3676QH(n=18, r=0.993) . QH is the net charge of the hydrogen atom in the imino group.