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A Benchmark Open-Source Implementation of COSMO-SAC



Ian H. Bell, Erik Mickoleit, Chieh-Ming Hsieh, Shiang-Tai Lin, Jadran Vrabec, Cornelia Breitkopf, Andreas J?ger


The COSMO-SAC modeling approach has found wide application in a range of industries due to its good predictive capabilities. While UNIFAC is in general more accurate than COSMO-SAC, the UNIFAC model contains many adjustable parameters and cannot be used if required group interaction parameters have not been fitted to experimental data or if a molecule cannot be subdivided into existing structural groups. In contrast, the COSMO-SAC model only contains a few universal parameters and subdivides the molecular surface area into charged segments that interact with each other. In recent years, additional improvements to the construction of the sigma profiles and evaluation of activity coefficients have been made. In this work, we present a comprehensive description how to postprocess the results of a COSMO calculation through to the evaluation of thermodynamic properties. We also assembled a large database of COSMO files, consisting of 2261 compounds, freely available to academic, noncommercial users. We especially focus on the documentation of the implementation and provide the optimized source code in C++, wrappers in Python, sample sigma profiles calculated from each approach, as well as tests and validation results. The misunderstandings in the literature relating to COSMO-SAC are described and corrected. The computational efficiency of the implementation is demonstrated.
Journal of Chemical Theory and Computation


Bell, I. , Mickoleit, E. , Hsieh, C. , Lin, S. , Vrabec, J. , Breitkopf, C. and J?ger, A. (2020), A Benchmark Open-Source Implementation of COSMO-SAC, Journal of Chemical Theory and Computation, [online], (Accessed May 19, 2024)


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Created February 13, 2020, Updated July 8, 2020