Abstract

Quantum chemical methods are used to calculate the electron density of molecules and positions of absorption bands of the N–H group of pyrrole, indole, carbazole in the presence and in the absence of H-complexes with an acetone molecule. It is established that the effectiveness of H-complex formation decreases together with the positive charge on the hydrogen atom of the N–H bond. The efficiency of H-bond formation is estimated by the low-frequency shift of the absorption peak corresponding to the N–H vibration of pyrrole derivatives. The obtained results suggest that the Coulomb component is not prevalent in the formation of H-complexes of pyrrole derivatives with acetone while the covalent component makes a more significant contribution.

中文翻译：

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根据红外光谱数据和量子化学计算研究吡咯衍生物与丙酮的 H 配合物的氢键性质

摘要

量子化学方法用于计算分子的电子密度和吡咯、吲哚、咔唑的 N-H 基团在丙酮分子存在和不存在 H 络合物的情况下的吸收带位置。已确定 H-配合物形成的有效性随着 N-H 键氢原子上的正电荷而降低。氢键形成的效率通过对应于吡咯衍生物的 N-H 振动的吸收峰的低频位移来估计。所得结果表明，库仑组分在吡咯衍生物与丙酮的 H-配合物的形成中并不普遍，而共价组分的贡献更为显着。