中文摘要：

利用太赫兹时域光谱（terahertz time-domain spectroscopy,简称THz-TDS）技术研究了次黄嘌呤及其核苷在0·3—1·6THz波段的光谱特性.结果显示THz波对该碱基及核苷的结构变化有灵敏响应,其中次黄嘌呤在该波段无特征吸收,而其核苷在1·4THz处有强的指纹特征吸收峰,根据Hartree-Fock模拟计算提示该低频振动来源于嘌呤环与戊糖环的扭摆振动.定量研究的结果表明,在一定浓度范围内所测化合物THz吸收强度与浓度呈线性关系,符合朗伯-比尔定律.利用THz谱成分分析法对次黄嘌呤及其核苷的混合物进行了定量解析,获得了混合物中各成分的含量,相对误差不超过7%,并就误差产生的原因做了简要分析.

英文摘要：

Far-infrared absorption spectra and refractive indices of hypoxanthine and inosine have been measured by terahertz time-domain spectroscopy （THz-TDS） in the frequency range of 0.3—1.6THz at room temperature. The experimental results show that there is a distinct difference between the THz absorption spectra of hypoxanthine and inosine,which suggests that THz-TDS is highly sensitive to molecular structures and the components. Hartree-Fork calculation was used to optimize and simulate the THz spectra obtained by measurement. The low frequency vibrational mode at 1.4 THz of inosine is attributed to the swing and torsion between purine and pentose rings according to the theoretical calculation. There is a linear relationship between the absorption intensity and the concentration of sample,which is consistent with Lambert-Beer＇s Law. Quantitative analysis of the components of mixtures of hypoxanthine and inosine was carried out by linear regression with non-negative constraint and the relative error was less than 7%. The sources of error were also discussed.