L-谷氨酸的量化计算研究

Study on Quantitative Calculation of L-Glutamic Acid

摘要: 本文利用b3lyp/6-31G(d))的方法对L-谷氨酸分子和离子的结构特点和红外光谱的分布规律进行了研究。研究发现根据分子振动类型的不同，L-谷氨酸的红外振动光谱主要分布在(0~800) cm^-1、(800~1350) cm^-1、(1350~2500) cm^-1和(2500~4000) cm^-1四个区域。与L-谷氨酸分子的红外振动光谱相比，L-谷氨酸离子的红外振动光谱在相同区域中谱线的整体强度、数目以及振动类型存在明显差异，谱线的最强峰和次强峰均出现了红移现象。此外，在两者的红外光谱中均存在无红外活性和简并的现象。

Abstract: The regularity of structural characteristics and infra-red spectrum distribution rules of L-glutamic acid molecular and ion are studied by the method of b3lyp/6-31G (d). After researched, the result shows that the infra-red spectrum of L-glutamic acid mainly lies in four different regions, according to vibration modes, which are (0 - 800) cm^-1, (800 - 1350) cm^-1, (1350 - 2500) cm^-1 and (2500 - 4000) cm^-1. Compared to the spectrum of L-glutamic acid, the intensity of the spectral line, number and the type of molecular vibration of L-glutamic acid ion has obvious difference. The strongest and secondary peaks of the spectral lines appear red shift. In addition, there is no infrared activity and degeneracy in both infrared spectrums.