Vehkamäki Hanna, Napari Ismo, Kulmala Markku, Noppel Madis
Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
Phys Rev Lett. 2004 Oct 1;93(14):148501. doi: 10.1103/PhysRevLett.93.148501. Epub 2004 Sep 28.
Liquid drop model based equilibrium thermodynamics predicts that in the presence of even small ammonia concentrations practically all the atmospheric sulfuric acid molecules are bound to tiny, stable ammonium-bisulfate clusters. Hitherto sulfuric acid has been believed to form hydrates with water. Thermodynamic theory predicts correctly the hydrate formation observed experimentally. Results from ab initio computer simulations contradict the thermodynamic results and also the experimental findings for cluster formation in both sulfuric acid-water and ammonia-sulfuric acid-water mixtures.
基于液滴模型的平衡热力学预测，即使在氨浓度很低的情况下，几乎所有大气中的硫酸分子都会与微小、稳定的硫酸氢铵团簇结合。在此之前，人们一直认为硫酸会与水形成水合物。热力学理论正确地预测了实验中观察到的水合物形成。从头算计算机模拟的结果与热力学结果以及硫酸 - 水和氨 - 硫酸 - 水混合物中团簇形成的实验结果相矛盾。
