The structural and energetic characteristics of the compounds formed by the reaction of diethylamine (DEA) with protic acids (sulfuric (H2SO4), methanesulfonic (MsOH), trifluoromethanesulfonic (TfOH), and para-toluenesulfonic (TsOH)) were examined using quantum chemical computations (B3LYP-GD3/6-31++G(d,p)). The strength of the hydrogen bonds in the ion pairs formed was quantitatively estimated by the QTAIM theory and NBO analysis. The results of the quantum chemical computations and the obtained thermal (phase transition and decomposition temperatures) and physicochemical (viscosity and conductivity) characteristics indicate that the reactions of DEA with the acids afford salts. The salts with the melting points higher than 100 °C are formed in the case of DEA/OTf(OTs), while protic ionic liquids are produced in the case of DEA/OMs(HSO4).

中文翻译：

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二乙胺基离子液体：量子化学计算与实验

使用量子化学计算检查了由二乙胺 (DEA) 与质子酸（硫酸 (H2SO4)、甲磺酸 (MsOH)、三氟甲磺酸 (TfOH) 和对甲苯磺酸 (TsOH)）反应形成的化合物的结构和能量特性(B3LYP-GD3/6-31++G(d,p))。形成的离子对中氢键的强度通过 QTAIM 理论和 NBO 分析进行定量估计。量子化学计算的结果和获得的热（相变和分解温度）和物理化学（粘度和电导率）特性表明 DEA 与酸反应生成盐。在DEA/OTf(OTs)的情况下形成熔点高于100°C的盐，而在DEA/OMs(HSO4)的情况下产生质子离子液体。