本文借助密度泛函理论中的B3LYP算法,基于6-31G(d)理论基组,深入探讨了甲氧氯普胺分子的结构特性,成功获取了其稳定的分子构象及红外光谱属性。研究揭示,甲氧氯普胺的红外振动光谱因振动模式的差异,主要分布于三个频率范围:低频段(0~500) cm−1、中频段(500~2000) cm−1和高频段(2000~4000) cm−1。此外,由于简并振动及非红外活性振动的存在,实际红外光谱中可辨识的谱线少于理论预测的简正振动数目。In this paper, the B3LYP algorithm within Density Functional Theory (DFT), based on the 6-31G(d) theoretical basis set, is employed to delve into the structural characteristics of the metoclopramide molecule. Stable molecular conformations and infrared spectral properties of metoclopramide are successfully obtained. The study reveals that the infrared vibrational spectrum of metoclopramide is mainly distributed across three frequency ranges due to different vibrational modes: the low-frequency range (0~500) cm−1, the mid-frequency range (500~2000) cm−1, and the high-frequency range (2000~4000) cm−1. Additionally, due to the presence of degenerate vibrations and non-infrared-active vibrations, the number of identifiable spectral lines in the actual infrared spectrum is less than the number of normal vibrations theoretically predicted.
