Theoretical Analysis on the Intramolecular Proton Transfer of Glycine and Diglycine and Their Water-containing Clusters

• Main Authors: Hsi-Kai Wang, 王璽凱
• Other Authors: Jyh-Chiang Jiang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/85713442234957251137

碩士 === 國立臺灣科技大學 === 化學工程系 === 93 === Proton transfer in the glycine, glycylglycine water-containing clusters has been investigated by using density functional theory at the B3LYP/6-31+G* level of theory. Two types of proton transfer, direct and through the water-bridge, in the neutral glycine and glyglycine water-containing clusters have been systematically studied. The calculated result demonstrated the direct proton migration from –COOH group to -NH2. Group is favorable in general, the energy barrier of proton transfer in surrounded water molecules increase. In addition, the proton transfer in the protonated N2-acety-N1-methylglycinamide water-containing clusters was also examined. The calculated result illustrates that the proton transfer through the two water-bridge is barrierless. As the number of the surrounded water molecules is larger than two, the excess proton will locate at water molecule during to the large PA of wate cluster than of N2-acetyl-N1-methylclycinamide.