Department of Experimental Physics, Comenius University Bratislava, Mlynská Dolina F2, 84248, Bratislava, Slovak Republic.
J Phys Chem A. 2010 Feb 4;114(4):1677-83. doi: 10.1021/jp906636b.
Formation of negative ions via dissociative electron attachment (DEA) to the amino acid serine in the gas phase was studied using two different crossed electron/molecular beam techniques and quantum chemical calculations. Resonance electron capture mass spectrum and effective ion yield curves of 16 negative ions were measured over the electron energy range from close to 0 to 11 eV. The negative ions from serine were detected from resonance states in the vicinity of 0, 1.3, 5, and 8 eV. The dominant reaction channel at low electron energies was (M-H)(-). The relative cross section for this ion exceeds more than 20 times that of any other fragment negative ions. A high-resolution experiment was applied to study fine structures in (M-H)(-) cross section. We have found that the second OH group influences some dissociative channels. Quantum chemical calculations were applied to interpret products of the DEA reaction channels.
利用两种不同的交叉电子/分子束技术和量子化学计算，研究了气相中氨基酸丝氨酸通过离解电子俘获（DEA）形成负离子的过程。在电子能量范围从接近 0 到 11 eV 内，测量了 16 种负离子的共振电子俘获质谱和有效离子产率曲线。在 0、1.3、5 和 8 eV 附近的共振态检测到丝氨酸的负离子。在低电子能量下，主要反应通道为（M-H）（-）。这种离子的相对截面超过其他任何碎片负离子的 20 倍以上。高分辨率实验用于研究（M-H）（-）截面中的精细结构。我们发现第二个 OH 基团影响了一些离解通道。量子化学计算被应用于解释 DEA 反应通道的产物。
