Development of SAFT-Based Coarse-Grained Models of Carbon Dioxide and Nitrogen

The Journal of Physical Chemistry B, Год журнала: 2025, Номер unknown

Опубликована: Март 21, 2025

We develop coarse-grained models for carbon dioxide (CO2) and nitrogen (N2) that capture the vapor–liquid equilibria of both their single components binary mixtures over a wide range temperatures pressures. To achieve this, we used an equation state (EoS), namely Statistical Associating Fluid Theory (SAFT), which utilizes molecular-based algebraic description free energy chain fluids. This significantly accelerates exploration parameter space, enabling development provide optimal macroscopic experimental data. SAFT creates fluids by chaining together spheres, represent parts molecule. The result is series fitted parameters, such as bead size, bond length, interaction strengths, seem amenable to molecular simulation. However, only limited set can be directly implemented in particle-based simulation; this predominantly due how handles overlap between bonded monomers with parameters do not translate physical features, length. lengths force-field, performed Wang–Landau transition-matrix Monte Carlo (WL-TMMC) simulations grand canonical ensemble on homonuclear fused two-segment Mie evaluated phase behavior at different lengths. In spirit law corresponding states, found force field, matches predictions, derived rescaling length scales based ratios critical point properties experiments. CO2 N2 was also investigated. Overall, excellent agreement pressures pure mixtures, similar TraPPE models. Our proposed approach first step establishing more robust bridge simulation modeling.

Язык: Английский

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Phase Equilibria of CO₂ and n-Alkanes in Bulk and Confined Space Using Parallelized Wang–Landau Transition-Matrix Monte Carlo Simulations

Energy & Fuels, Год журнала: 2025, Номер unknown

Опубликована: Апрель 6, 2025

Язык: Английский

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Anisotropic coarse-grain Monte Carlo simulations of lysozyme, lactoferrin, and NISTmAb by precomputing atomistic models

The Journal of Chemical Physics, Год журнала: 2024, Номер 161(9)

Опубликована: Сен. 5, 2024

We develop a multiscale coarse-grain model of the NIST Monoclonal Antibody Reference Material 8671 (NISTmAb) to enable systematic computational investigations high-concentration physical instabilities such as phase separation, clustering, and aggregation. Our coarse-graining strategy captures atomic-resolution interactions with approach that is orders magnitude more efficient than atomistic models, assuming biomolecule can be decomposed into one or rigid bodies known, fixed structures. This method reduces between tens thousands atoms single anisotropic interaction site. The unique pairs precomputed over discrete set relative orientations stored, allowing arbitrarily oriented interpolated from table during coarse-grained Monte Carlo simulations. present this for lysozyme lactoferrin body NISTmAb three bound by flexible hinge an implicit solvent model. predicts experimentally measured radius gyration second osmotic virial coefficient data, enabling routine simulation medically relevant concentrations interacting proteins while retaining detail. All methodologies used in work are available open-source software Free Energy Advanced Sampling Simulation Toolkit.

Язык: Английский

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Extracting Orientation and Distance-Dependent Interaction Potentials between Proteins in Solutions Using Small-Angle X-ray/Neutron Scattering

The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер 15(50), С. 12401 - 12407

Опубликована: Дек. 10, 2024

Nonspecific protein-protein interactions (PPIs) are key to understanding the behavior of proteins in solutions. However, experimentally measuring anisotropic PPIs as a function orientation and distance has been challenging. Here, we propose measure new parameter, generalized second virial coefficient,

Язык: Английский

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