从天体物理上相关的冰中对CO的红外光电吸收被用自由电子激光研究
Emily R Ingman1, Domantas Laurinavicius2, Jin Zhang3
1Department of Chemistry, University of Sussex, Falmer, Brighton, BN1 9QJ, UK. w.a.brown@sussex.ac.uk.
Faraday discussions
|June 14, 2023
概括
红外线可以使一氧化碳 (CO) 从水冰中摄影吸收,但只有当它与水的振动共振时,而不是CO. 这个过程改变了冰的结构,涉及间接和基板介导的机制.
科学领域:
- 天体化学是天体化学.
- 表面科学是一门学科.
- 摄影化学的使用.
背景情况:
- 一氧化碳 (CO) 和水 (H2O) 是星际冰中的丰富分子.
- 了解它们的光化学对于天体化学模型至关重要.
- 之前的研究已经探索了各种冰的光电吸收.
研究的目的:
- 调查CO-水混合冰中的红外诱导的CO光分解.
- 确定负责CO光电吸收的波长和机制.
- 描述辐射后冰结构的变化.
主要方法:
- 使用自由电子激光器 (FEL-2) 对CO-水冰进行红外辐射.
- 在18K的金铜基板上生长混合冰.
- 使用敏感检测方法分析光电吸收.
主要成果:
- 在CO振动模式 (4.67μm) 照射时没有观察到CO光电吸收.
- 在用水振动模式 (2.9微米和12微米) 照射后发生了CO光电吸收.
- 水冰结构发生了变化,影响了二氧化碳环境;没有观察到水溶解.
结论:
- 从水冰中二氧化碳的红外光吸收是间接的,并且取决于波长.
- 机制包括间接共振光吸附和基板介导的热吸附.
- 这些发现为天体物理环境中的冰处理提供了洞察力.
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