Collisions of protic and aprotic gases with hydrogen bonding and hydrocarbon liquids
Collisions of protic and aprotic gases with hydrogen bonding and hydrocarbon liquids
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质子和非质子气体与氢键和碳氢化合物液体的碰撞
DOI：
10.1063/1.465425
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发表时间：
1993
影响因子：
4.4
通讯作者：
G. Nathanson
中科院分区：
文献类型：
--
作者：
Mary E. Saecker;G. Nathanson
我们探索 Ne、CH4、NH3 和 D2O 与甘油（一种氢键液体）以及与角鲨烷（一种液态烃）的碰撞。实验是通过将分子束引导到真空中不断更新的液体表面并通过质谱监测散射产物的特性和速度来进行的。当气体撞击液体时，我们观察到直接非弹性散射和捕获解吸。多原子气体在低碰撞能量下容易热化，但随着入射能量的增加而更频繁地反弹。我们发现脉冲能量传递是广泛的，并且仅微弱地依赖于气体或液体的类型；对于导致直接散射的相遇，气体似乎与角鲨烷的 CH2 和 CH3 基团以及甘油的 OH 和 CH2 基团发生硬球状碰撞。然而，这些气体在两种液体上的适应情况不同：氖气和甲烷在角鲨烷上的平衡效率更高，氨在每种液体上的热化效果相同，而水更容易被甘油捕获。捕获概率的差异小于它们溶解度的预期差异，但它们大致遵循自由能和溶剂化焓的趋势。我们的研究结果表明，气液碰撞中的热调节反映了碳氢化合物的机械粗糙度和柔软度，以及质子气体和甘油的羟基之间的强大吸引力。我们探索了 Ne、CH4、NH3 和 D2O 与甘油（一种氢键液体）以及角鲨烷（一种液体碳氢化合物）的碰撞。实验是通过将分子束引导到真空中不断更新的液体表面并通过质谱监测散射产物的特性和速度来进行的。当气体撞击液体时，我们观察到直接非弹性散射和捕获解吸。多原子气体在低碰撞能量下容易热化，但随着入射能量的增加而更频繁地反弹。我们发现脉冲能量传递是广泛的，并且仅微弱地依赖于气体或液体的类型；对于导致直接散射的相遇，气体似乎与角鲨烷的 CH2 和 CH3 基团以及甘油的 OH 和 CH2 基团发生硬球状碰撞。然而，这些气体在两种液体上的适应情况不同：氖气和甲烷在角鲨烷上更有效地达到平衡，氨在每种液体上的热化效果相同，...
We explore collisions of Ne, CH4, NH3, and D2O with glycerol, a hydrogen bonding liquid, and with squalane, a liquid hydrocarbon. The experiments are carried out by directing a molecular beam at a continuously renewed liquid surface in vacuum and monitoring the identity and velocity of the scattered products with mass spectroscopy. We observe both direct inelastic scattering and trapping desorption when the gases strike the liquids. The polyatomic gases thermalize readily at low collision energies but rebound more frequently as the incident energy increases. We find that impulsive energy transfer is extensive and depends only weakly on the type of gas or liquid; for encounters leading to direct scattering, the gases appear to undergo hard spherelike collisions with the CH2 and CH3 groups of squalane and the OH and CH2 groups of glycerol. The gases accommodate differently on the two liquids, however: Neon and methane equilibrate more efficiently on squalane, ammonia thermalizes equally well on each liquid, and water is trapped more frequently by glycerol. The differences in trapping probabilities are smaller than expected from their solubilities, but they roughly follow trends in the free energies and enthalpies of solvation. Our results suggest that thermal accommodation in gas–liquid collisions reflects both the mechanical roughness and softness of hydrocarbons and the strong attractive forces between protic gases and the OH groups of glycerol.We explore collisions of Ne, CH4, NH3, and D2O with glycerol, a hydrogen bonding liquid, and with squalane, a liquid hydrocarbon. The experiments are carried out by directing a molecular beam at a continuously renewed liquid surface in vacuum and monitoring the identity and velocity of the scattered products with mass spectroscopy. We observe both direct inelastic scattering and trapping desorption when the gases strike the liquids. The polyatomic gases thermalize readily at low collision energies but rebound more frequently as the incident energy increases. We find that impulsive energy transfer is extensive and depends only weakly on the type of gas or liquid; for encounters leading to direct scattering, the gases appear to undergo hard spherelike collisions with the CH2 and CH3 groups of squalane and the OH and CH2 groups of glycerol. The gases accommodate differently on the two liquids, however: Neon and methane equilibrate more efficiently on squalane, ammonia thermalizes equally well on each liquid,...