用衰减全反射傅里叶光谱仪(FTIR-ATR)在室温条件下测试了甲醇、乙醇、丙醇、异丙醇、丁醇及异丁醇六种饱和一元醇在30~300 cm~(-1)波段的远红外透射光谱。通过分析这六种具有类似化学结构的一元醇的远红外透射光谱,发现它们在30~150 cm~(-1)波段均有明显的吸收峰,但在150~300 cm~(-1)波段吸收峰不明显;羟基在一元醇中的质量百分比越高,相关一元醇的远红外光谱的平均透过率越低;直链一元醇的光谱平均透过率高于支链状的同分异构体。采用密度泛函理论B3LYP/6-311G(d,p)基组对甲醇单体和多聚体进行结构优化和频率计算。计算显示,在30~150 cm~(-1)波段甲醇单体分子没有出现吸收峰,但是甲醇的多聚体则出现明显的吸收峰,计算得到的多聚体吸收峰位置与实际测量的结果相符合。结果表明,甲醇在太赫兹波段吸收的来自于不同形式聚合体的集体振动,甲醇溶液以甲醇三聚体为主要的存在形式。本成果不仅为研究有机分子在太赫兹波段的频率响应提供了新的实验方法,而且对进一步利用FTIR-ATR研究其他有机分子具有借鉴意义。 Six saturated monoalcohols such as methanol, ethanol, propanol, isopropanol, butanol and isobutanol were tested at room temperature for 30 ~ 300 cm ~ (-1) with attenuated total reflection Fourier spectroscopy (FTIR-ATR) ) Far-infrared transmission spectrum of the band. By analyzing the far infrared transmission spectra of these six kinds of monoalcohols with similar chemical structure, they all showed obvious absorption peaks in the range of 30-150 cm -1, but in the band of 150-300 cm -1 The absorption peak is not obvious; the higher the mass percentage of hydroxyl in the monohydric alcohol, the lower the average transmittance of the related monoalcohol in the far infrared spectrum; the average spectral transmittance of the straight monoalcohol is higher than that of the branched Structure. The structure optimization and frequency calculation of methanol monomer and multimer were carried out using the B3LYP / 6-311G (d, p) basis set of density functional theory. Calculations show that there is no absorption peak at 30-150 cm -1 but there is a significant absorption peak at the methanol multimer, and the calculated polymer absorption peak position and actual measurement result Match. The results show that the methanol in the terahertz band absorbs from different forms of aggregate vibration, methanol solution to the methanol trimer as the main form of existence. This result not only provides a new experimental method for studying the frequency response of organic molecules in the terahertz band, but also provides reference for the further study of other organic molecules by FTIR-ATR.