Search for: solvation-free-energy
Solvation free energy and solubility of acetaminophen and ibuprofen in supercritical carbon dioxide: Impact of the solvent model, Article Journal of Supercritical Fluids ; Volume 109 , 2016 , Pages 166-176 ; 08968446 (ISSN) ; Ghotbi, C ; Jahanbin Sardroodi, J ; Karimi Sabet, J ; Robert, M. A ; Sharif University of Technology
Classical molecular dynamics simulations are used to compute the solvation free energy of two pharmaceutical solids, namely ibuprofen and acetaminophen in carbon dioxide (CO2), over the density range of interest in supercritical processes. In order to examine the influence of the solvent model on the resulting free energies, three popular CO2 models (Zhang, EPM2, and TraPPE) are studied. Relatively large discrepancies for the solvation free energy exist between these CO2 models, suggesting that the former is sensitive to the different balances between dispersive and electrostatic forces used in these models. In particular, for the solvation of the highly polar (dipole moment of ∼5.2 Debye)...
Microscopic structure and solubility predictions of multifunctional solids in supercritical carbon dioxide: a molecular simulation study, Article Journal of Physical Chemistry B ; Volume 121, Issue 7 , 2017 , Pages 1660-1674 ; 15206106 (ISSN) ; Paluch, A. S ; Sharif University of Technology
Molecular dynamics simulations were employed to both estimate the solubility of nonelectrolyte solids, such as acetanilide, acetaminophen, phenacetin, methylparaben, and lidocaine, in supercritical carbon dioxide and understand the underlying molecular-level driving forces. The solubility calculations involve the estimation of the solute's limiting activity coefficient, which may be computed using conventional staged free-energy calculations. For the case of lidocaine, wherein the infinite dilution approximation is not appropriate, we demonstrate how the activity coefficient at finite concentrations may be estimated without additional effort using the dilute solution approximation and how...