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COSMO-RS
What is COSMO-RS/SAC
The COnductor-like Screening MOdel for Realistic Solvents calculates thermodynamic properties of fluids and solutions based on quantum mechanical data. Properties from COSMO-RS have predictive power outside the parametrization set, as opposed to empirical models (e.g. UNIFAC).
The recent reparametrization of COSMO-SAC (segmented activity coefficients) model by Stan Sandler’s group improves partition coefficients (logP) for a set of solvent combinations. Furthermore, vapor-liquid equilibrium predictions are improved yielding a better agreement between calculated and experimental vapor pressures of mixtures.
Instantaneous thermodynamic property prediction
A database of over 2500 compounds containing solvents & small molecules (list) and ionic liquids (list, tutorial ionic liquids) facilitates instantaneous predictions of log P, solubilities, and other properties. It is easy to add new molecules to the database using a dedicated ADF template or ad-hoc estimation directly from SMILES strings.
Step-by-step Tutorials show how to set up COSMO-RS property calculations with the GUI and our Scripting tools enable rapid solvent screening.
Solvent optimization
Chemical engineers may want to optimize distillation processes by tweaking vapor pressures and boiling points, while medicinal chemists perhaps want to maximize solvent extraction efficiency to separate the active pharmaceutical ingredient from its main contaminant, or maximize solubility with excipients.
Our solvent system optimization tool is perfectly placed to help reduce the experimental search space by optimizing solvent mixtures for solubility or liquid-liquid extraction across a set of selected solvents.
Applications for scripting with COSMO-RS/SAC include optimizing catalysts, solubility parameters, pKa values and sorption in ionic liquids.
Conformers, aggregates, protonation states
Since AMS2020, you can deal with more complex solution behavior where compounds may behave differently in various solvents or under different conditions. These include cases where the solute dissociates, aggregates, or has multiple conformers (seeTutorial).
Polymers
COSMO-RS and COSMO-SAC predict thermodynamic properties and descriptors for polymers such as activity coefficients, vapor pressures, partition coefficients, solubilities, and Flory-Huggins Chi. In combination with the new polymer builder of the graphical user interface, these new features significantly extend our polymer tools since AMS2019.
Features
- solubilities, partition coefficients (log P, log kOW)
- pKa values (empirical fit improves predictions: Tutorial)
- activity coefficients, solvation free energies, Henry’s law constants
- vapor pressures, boiling points, vapor-liquid diagrams binary and ternary mixtures (VLE/LLE)
- excess energies, azeotropes, miscibility gaps
- composition lines, flash points
- quick sigma profiles for COSMO-RS & COSMO-SAC
- UNIFAC & QSPR prediction of many properties
- optimizing solvent mixtures for solubility or extraction
Applications
Videos
Solvent optimization for liquid-liquid extraction with AMS COSMO-RS
A small demonstration of how to use COSMO-RS to optimize solvents for liquid-liquid extraction.
AMS2018 – COSMO-RS new features: quick predictions & solvent optimization
Let SCM developer Nick Austin walk you through the newest COSMO-RS related features in AMS2018.
Thermodynamic Properties for Polymer solutions with COSMO-RS(-SAC)
We showcase the capabilities of our COSMO-RS module in the Amsterdam Modeling Suite for predicting the thermodynamic properties of polymer-containing solutions.