在星际介质中形成甘氨酸的气相形成
Luis Guerrero-Méndez1, Anxo Lema-Saavedra2, Elena Jiménez3,4
1Departamento de Química Física, Facultade de Química, Universidade de Santiago de Compostela, Avda. das Ciencias s/n 15782, Santiago de Compostela, Spain. qf.ramos@usc.es.
Physical chemistry chemical physics : PCCP
|July 28, 2023
概括
自动反应发现确定了在星际介质中形成甘尼和异酸的有效途径. 这些发现可能解释了异酸的过剩.
科学领域:
- 天体化学是天体化学.
- 化学动力学 化学动力学
- 计算化学计算化学
背景情况:
- 星际介质 (ISM) 中复杂有机分子的形成对于理解前生物化学至关重要.
- 在ISM中观察到甘尼铁 (HOCH2CN) 和同化 (HNC),但它们的形成途径仍在争论中.
- 低温和富含激素的ISM环境为化学合成带来了独特的挑战.
研究的目的:
- 通过使用计算方法,研究星际介质中的甘尼特的气相形成.
- 在ISM条件下识别可行的激素-激素和激素-分子反应途径.
- 探讨在ISM中观察到的异酸过剩的潜在解释.
主要方法:
- 利用自动反应发现程序AutoMeKin进行理论研究.
- 为拟议的反应计算了反应路径,能量障碍和速率系数.
- 在星际介质条件下 (10-150 K) 评估了前体的可用性和反应的可行性.
主要成果:
- 确定OH + CH2CN作为一个重要的根基-根基通路,形成甘尼铁,但也产生高效率的HNC和甲 (CH2O).
- 确定OH + CH2CN反应的速率系数为 (7.3-11.5) × 10^-10 cm^3 分子^-1 s^-1.
- 确定OH + CH2CHNH作为一个有前途的激素分子通路,形成0.3-6.6的速率系数的甘尼铁和原子10^-10cm^3分子^-1s^-1.
结论:
- OH + CH2CN反应为HNC的形成提供了一个合理和有效的途径,可能解释其ISM过剩.
- 通过研究的途径,在星际条件下,甘尼和异化都能有效地形成.
- 这项研究扩大了在ISM中HNC形成的可行激进-激进机制的范围.
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