Abstract

The mechanism of radiation damage to 2,5-diketopiperazine (DKP, C₄H₆N₂O₂) molecules in the gas phase upon interaction with He²⁺ ions with an energy Ep = 4 keV/u has been investigated. The relative cross sections of various elementary processes occurring in single collisions of DKP with ions have been measured for the first time. The channels of fragmentation processes of singly charged ions have been studied experimentally. The DFT method was used to calculate the geometry of molecules and singly charged DKP ions, as well as the energies of the main experimentally observed channels of fragmentation of these ions.

中文翻译：

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2,5-二酮哌嗪环状二肽离子的断裂

摘要

研究了气相中的2,5-二酮哌嗪 (DKP, C ₄ H ₆ N ₂ O ₂ ) 分子与能量Ep = 4 keV/u 的 He ^{2+离子相互作用时的辐射损伤机制。}首次测量了 DKP 与离子单次碰撞中发生的各种基本过程的相对截面。通过实验研究了单电荷离子的碎裂过程通道。DFT 方法用于计算分子和单电荷 DKP 离子的几何形状，以及实验观察到的主要离子碎裂通道的能量。