Hoelzl, Christoph and Kibies, Patrick and Imoto, Sho and Noetzel, Jan and Knierbein, Michael and Salmen, Paul and Paulus, Michael and Nase, Julia and Held, Christoph and Sadowski, Gabriele and Marx, Dominik and Kast, Stefan M. and Horinek, Dominik (2019) Structure and thermodynamics of aqueous urea solutions from ambient to kilobar pressures: From thermodynamic modeling, experiments, and first principles simulations to an accurate force field description. BIOPHYSICAL CHEMISTRY, 254: 106260. ISSN 0301-4622, 1873-4200
Full text not available from this repository. (Request a copy)Abstract
Molecular simulations based on classical force fields are a powerful method for shedding light on the complex behavior of biomolecules in solution. When cosolutes are present in addition to water and biomolecules, subtle balances of weak intermolecular forces have to be accounted for. This imposes high demands on the quality of the underlying force fields, and therefore force field development for small cosolutes is still an active field. Here, we present the development of a new urea force field from studies of urea solutions at ambient and elevated hydrostatic pressures based on a combination of experimental and theoretical approaches. Experimental densities and solvation shell properties from ab initio molecular dynamics simulations at ambient conditions served as the target properties for the force field optimization. Since urea is present in many marine life forms, elevated hydrostatic pressure was rigorously addressed: densities at high pressure were measured by vibrating tube densitometry up to 500 bar and by X-ray absorption up to 5 kbar. Densities were determined by the perturbed-chain statistical associating fluid theory equation of state. Solvation properties were determined by embedded cluster integral equation theory and ab initio molecular dynamics. Our new force field is able to capture the properties of urea solutions at high pressures without further high-pressure adaption, unlike trimethylamine-N-oxide, for which a high-pressure adaption is necessary.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | KIRKWOOD-BUFF INTEGRALS; PERTURBED-CHAIN SAFT; MOLECULAR-DYNAMICS; IONIC LIQUIDS; DERIVATIVE PROPERTIES; SODIUM-CHLORIDE; FREE-ENERGY; AMINO-ACID; PC-SAFT; WATER; |
| Subjects: | 500 Science > 540 Chemistry & allied sciences |
| Divisions: | Chemistry and Pharmacy > Institut für Physikalische und Theoretische Chemie > Chair of Chemistry VI - Physical Chemistry (Solution Chemistry) > Prof. Dr. Dominik Horinek |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 25 Mar 2020 09:40 |
| Last Modified: | 06 Apr 2020 06:16 |
| URI: | https://pred.uni-regensburg.de/id/eprint/25885 |
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