How Many Methanol Molecules Can Solvate a Glycine: a PBE1PBE Approach  

作　　者：王红磊 邹昊 胡勇军 

机构地区：[1]MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University

出　　处：《Chinese Journal of Structural Chemistry》2011年第11期1656-1671,共16页结构化学（英文）

基　　金：supported by NNSFC (No. 20973067 and 11079020);Guangdong-NSF grants (No. 7005823);the scientific research foundation for the returned overseas Chinese scholars, State Education Ministry;the foundation for introduction of talents by the universities in Guangdong Province

摘　　要：Microsolvation of glycine in methanol clusters is explored by the use of DFT calculation method. The lowest energy conformations within 16.72 kJ·mol^-1 of the glycine clustering with one to six methanol molecules, which are obtained at the B3LYP/6-31＋G（d） level of theory, are reoptimized at PBE1PBE/6-311＋G（d,p）. The calculated results agree with our previous results with B3LYP （Chin. J. Chem. Phys. 22 （2009） 577） that the clusters of two forms （Z- and N-form） tend to be isoenergetic when the number of the solvate molecules reaches six. Furthermore, this result is in good agreement with the experiment of the tryptophan-methanol clusters, implying that the present treatments are reasonable and reliable. The results also indicate that nine methanol molecules are not enough to fully solvate a glycine molecule, and a tentative estimation is obtained that ten methanol molecules may fully solvate a glycine molecule, which consists with the experiment results.Microsolvation of glycine in methanol clusters is explored by the use of DFT calculation method. The lowest energy conformations within 16.72 kJ·mol^-1 of the glycine clustering with one to six methanol molecules, which are obtained at the B3LYP/6-31＋G（d） level of theory, are reoptimized at PBE1PBE/6-311＋G（d,p）. The calculated results agree with our previous results with B3LYP （Chin. J. Chem. Phys. 22 （2009） 577） that the clusters of two forms （Z- and N-form） tend to be isoenergetic when the number of the solvate molecules reaches six. Furthermore, this result is in good agreement with the experiment of the tryptophan-methanol clusters, implying that the present treatments are reasonable and reliable. The results also indicate that nine methanol molecules are not enough to fully solvate a glycine molecule, and a tentative estimation is obtained that ten methanol molecules may fully solvate a glycine molecule, which consists with the experiment results.

关 键 词：DFT MICROSOLVATION gibbs free energy amino acid GLYCINE 

分 类 号：O621.2[理学—有机化学]