采用太赫兹时域光谱 (THz-TDS)技术测量了乳清酸在 10~120 cm-1的室温特征吸收谱; 基于密度泛函理论, 对乳清酸单个分子和晶胞周期结构的光学模式进行模拟计算。研究结果表明: 乳清酸在10~120 cm-1波段范围内有 3个明显的特征吸收峰, 除 95.5 cm-1的吸收峰来源于分子内和分子间相互作用外, 其余 2个特征吸收峰主要来源于分子间相互作用模式。乳清酸分子间的相互作用一定程度上遏制了其分子内振动强度。该研究将有助于工业生产中乳清酸的监测及其临床药理特性的分析。

The THz spectrum of orotic acid is measured in the range of 10-120 cm-1 by using Terahertz Time-Domain Spectroscopy(THz-TDS). The result shows three distinct THz absorption features which are interpreted by density functional theory. It is found that the feature at 95.5 cm-1 originates from the combination of intermolecular and intramolecular vibrational modes while the rest two features come from the rotational modes. Besides, the intermolecular interactions of orotic acid may minimize the intramolecular interactions to a certain extent. These results may be helpful to the monitoring of orotic acid in the industrial production and its study on pharmacological characteristics.