期刊
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
卷 21, 期 27, 页码 14799-14810出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/c9cp01572h
关键词
-
资金
- Ministry of Education, Youth and Sports of the Czech Republic, a part of the INTER-EXCELLENCE program [LTAUSA18011]
- Large Infrastructures for Research, Experimental Development and Innovations project IT4Innovations National Super-computing Center [LM2015070]
- United States National Science Foundation [CHE1665212]
- XSEDE [TG-CHE110064]
Knowledge of molecular crystal sublimation equilibrium data is vital in many industrial processes, but this data can be difficult to measure experimentally for low-volatility species. Theoretical prediction of sublimation pressures could provide a useful supplement to experiment, but the exponential temperature dependence of sublimation (or any saturated vapor) pressure curve makes this challenging. An uncertainty of only a few percent in the sublimation enthalpy or entropy can propagate to an error in the sublimation pressure exceeding several orders of magnitude for a given temperature interval. Despite this fundamental difficulty, this paper performs some of the first ab initio predictions of sublimation pressure curves. Four simple molecular crystals (ethane, methanol, benzene, and imidazole) have been selected for a case study showing the currently achievable accuracy of quantum chemistry calculations. Fragment-based ab initio techniques and the quasi-harmonic approximation are used for calculations of cohesive and phonon properties of the crystals, while the vapor phase is treated by the ideal gas model. Ab initio sublimation pressure curves for model compounds are compared against their experimental counterparts. The computational uncertainties are estimated, weak points of the computational methodology are identified, and further improvements are proposed.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据