| Title: | Quantum chemical calculation of the vapor pressure of volatile and semi volatile organic compounds |
| Author(s): | Stahn M; Grimme S; Salthammer T; Hohm U; Palm WU; |
| Address: | "Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, 53115 Bonn, Germany. Department of Material Analysis and Indoor Chemistry, Fraunhofer WKI, 38108 Braunschweig, Germany. tunga.salthammer@wki.fraunhofer.de. Institute of Physical and Theoretical Chemistry, University of Braunschweig - Institute of Technology, 38106 Braunschweig, Germany. Institute of Sustainable and Environmental Chemistry, Leuphana University Luneburg, 21335 Luneburg, Germany" |
| Journal Title: | Environ Sci Process Impacts |
| ISSN/ISBN: | 2050-7895 (Electronic) 2050-7887 (Linking) |
| Abstract: | "The vapor pressure is a specific and temperature-dependent parameter that describes the volatility of a substance and thus its driving force for evaporation or sublimation into the gas phase. Depending on the magnitude of the vapor pressure, there are different methods for experimental determination. However, these are usually associated with a corresponding amount of effort and become less accurate as the vapor pressure decreases. For purposes of vapor pressure prediction, algorithms were developed that are usually based on quantitative structure-activity relationships (QSAR). The quantum mechanical (QM) approach followed here applies an alternative, much less empirical strategy, where the change in Gibbs free energy for the transition from the condensed to the gas phase is obtained from conformer ensembles computed for each phase separately. The results of this automatic, so-called CRENSO workflow are compared with experimentally determined vapor pressures for a large set of environmentally relevant compounds. In addition, comparisons are made with the single structure-based COSMO-RS QM approach, linear-free-energy relationships (LFER) as well as results from the SPARC program. We show that our CRENSO workflow is superior to conventional prediction models and provides reliable vapor pressures for liquids and sub-cooled liquids over a wide pressure range" |
| Keywords: | *Volatile Organic Compounds Vapor Pressure Phase Transition Temperature Algorithms; |
| Notes: | "MedlineStahn, Marcel Grimme, Stefan Salthammer, Tunga Hohm, Uwe Palm, Wolf-Ulrich eng England 2022/10/13 Environ Sci Process Impacts. 2022 Nov 16; 24(11):2153-2166. doi: 10.1039/d2em00271j" |
