A study is performed of IR absorption and Raman spectra of methyl 6-methoxy-2,3,4,9-tetrahydro-1H-1,4-ethanocarbazole-3-carboxylate. Optimized structures and the harmonic force fields of stable conformers are calculated using the density functional theory (the B3LYP, M062X, and BVP86 functionals combined with basis sets of different completeness). A detailed explanation of the spectra is proposed based on calculations, and the characteristic frequencies of the most stable forms of a given compound are identified. The theoretical spectra are analyzed relative to experimental data.

中文翻译：

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6-甲基甲氧基-2,3,4,9-四氢-1H-1,4-乙基咔唑-3-羧酸甲酯的振动光谱和稳定构象

对6-甲氧基-2,3,4,9-四氢-1H-1,4-乙基咔唑-3-羧酸甲酯的红外吸收和拉曼光谱进行了研究。使用密度泛函理论（B3LYP，M062X和BVP86泛函结合不同完整性的基础集）来计算稳定构象体的优化结构和谐波力场。根据计算结果，对光谱进行了详细说明，并确定了给定化合物最稳定形式的特征频率。相对于实验数据分析理论光谱。