D2O通过与Ar原子的碰撞而发生的振动放松
1Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia.
The Journal of chemical physics
|March 9, 2026
概括
通过对 (Ar) 的碰撞来研究化水 (D2O) 的振动放松. 发现D2O放松速度比H2O慢3-5倍,尽管能量差距较小.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 分子光谱学 分子光谱学
背景情况:
- 振动能量转移对于理解化学反应和大气过程至关重要.
- 化水 (D2O) 与其相对应物 (H2O) 相比,具有不同的振动特性.
- 以前对Ar的H2O放松的研究提供了比较的基础.
研究的目的:
- 研究D2O分子在与Ar原子碰撞时处于激发状态 (v2,v13) 的振动放松动态.
- 为了确定D2O-Ar相互作用的特定状态振动放松速率常数.
- 将D2O的放松行为与H2O的放松行为进行比较.
主要方法:
- 通过外热反应和单分子分解生成振动激发的D2O分子.
- 在不同Ar压力和反应时间下的快速流动反应堆中观察D2O红外辐射.
- 动力分析比较实验振动分布与数值模拟来推导速率常数.
主要成果:
- 通过Ar获得了D2O振动放松的州特定速率常数.
- 从拉伸状态 (01) 到 (04) 确定了平均损失率常数.
- 测量了第一个曲状态 (v2=1,v13=0) 的放松率常数,并发现与先前的数据一致.
- 较高曲状态的速率常数在v2时呈现线性增加,在v13时呈现轻微下降.
- 发现D2O放松速率常数比H2O的3-5倍小.
结论:
- D2O通过Ar的振动放松明显比H2O慢得多.
- 速率常数观察到的趋势表明它依赖于振动量子数 (v2和v13).
- 这些发现有助于更深入地了解同位素变体中的分子能量转移过程.
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