Wasowicz Tomasz J, Pranszke Bogusław
Department of Physics of Electronic Phenomena, Gdańsk University of Technology , ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland.
Institute of Experimental Physics, University of Gdańsk , ul. Wita Stwosza 59, 80-952 Gdańsk, Poland.
J Phys Chem A. 2016 Feb 25;120(7):964-71. doi: 10.1021/acs.jpca.5b11298. Epub 2016 Feb 10.
The ability to selectively control chemical reactions related to biology, combustion, and catalysis has recently attracted much attention. In particular, the hydrogen atom relocation may be used to manipulate bond-breaking and new bond-forming processes and may hold promise for far-reaching applications. Thus, the hydrogen atom migration preceding fragmentation of the gas-phase pyridine molecules by the H(+), H2(+), He(+), He(2+), and O(+) impact has been studied experimentally in the energy range of 5-2000 eV using collision-induced luminescence spectroscopy. Formation of the excited NH(A(3)Π) radicals was observed among the atomic and diatomic fragments. The structure of the pyridine molecule is lacking of the NH group, therefore observation of its A(3)Π → X(3)Σ(-) emission bands is an evidence of the hydrogen atom relocation prior to the cation-induced fragmentation. The NH(A(3)Π) emission yields indicate that formation of the NH radicals depends on the type of selected projectile and can be controlled by tuning its velocity. The plausible collisional mechanisms as well as fragmentation channels for NH formation in pyridine are discussed.
选择性控制与生物学、燃烧和催化相关的化学反应的能力最近备受关注。特别是，氢原子重排可用于操纵键断裂和新键形成过程，并可能具有广泛应用前景。因此，利用碰撞诱导发光光谱，在5 - 2000 eV能量范围内对H(+)、H2(+)、He(+)、He(2+)和O(+)撞击气相吡啶分子使其碎片化之前的氢原子迁移进行了实验研究。在原子和双原子碎片中观察到了激发态NH(A(3)Π)自由基的形成。吡啶分子结构中不存在NH基团，因此观察到其A(3)Π → X(3)Σ(-)发射带是阳离子诱导碎片化之前氢原子重排的证据。NH(A(3)Π)发射产率表明NH自由基的形成取决于所选入射粒子的类型，并且可以通过调节其速度来控制。文中讨论了吡啶中NH形成的合理碰撞机制以及碎片化通道。
