紫外线诱导的转变和自发的原子道化在低温Ar矩阵中分离的2-甲中
Hanna Rostkowska1, Katarzyna Kulik2, Anna Luchowska1
1Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland.
概括
在基矩阵中对2-甲单体进行紫外线照射,引发了陶托马转换. 一种oxo-selenol形式通过原子道自发地回归到oxo-selenone tautomer.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 量子化学 是一个量子化学.
背景情况:
- 2 - 甲存在于各种各样的复合体形式,其中oxoselenone形式是最稳定的.
- 了解含核基的光化学行为和分体化对于各种化学和生物应用至关重要.
研究的目的:
- 为了研究在基矩阵中分离的2-甲单体的紫外线诱导的陶托马转化.
- 阐明自发性分离的机制,特别是原子道的作用.
主要方法:
- 在低温 (12K) 阿贡矩阵中对2-甲单体的气相隔离.
- 用不同波长的紫外线照射 (λ > 345 nm 和 λ = 305 nm).
- 使用红外 (IR) 光谱识别和与理论 DFT 和 MP2 计算进行比较.
- 确定自发分离的时间常数.
主要成果:
- 紫外线照射 (λ > 345 nm) 将氧-烯 tautomer 转化为一种氧-烯形式.
- 较短波长的紫外线照射 (λ = 305 nm) 产生了两种更高能量的光产物:另一种氧-醇和一种-醇形式.
- 观察到光生成的oxo-selenol自发转化回到oxo-selenone分离体,由原子道化驱动,时间常数为39±3小时.
结论:
- 在紫外线照射下,2-甲会经历明显的分体变化,这取决于波长.
- 原子道化被证实是低温下氧二醇自发逆转为氧二醇复合体的驱动力.
- 这项研究提供了关于含异环的光化学和分体的宝贵见解.
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