EPISOL

EPISOL performs solvation modeling using 3D-reference interaction site model (3D-RISM) and integral equation theory (IET) to compute solvation density distributions and solvent free energies for chemical and biological systems.

Key Features:

• 3D-RISM and IET: Implements 3D-reference interaction site model (3D-RISM) within integral equation theory (IET) to model three-dimensional solvation structure.
• Closures and free energy functionals: Supports 22 different closures and multiple free energy functionals for diverse solvation calculations.
• Extended theoretical variants: Includes hydrophobicity-induced density inhomogeneity (HI) theory for hydrophobic solutes and ion-dipole correction (IDC) theory for negatively charged solutes.
• Numerical stability and convergence: Employs numerical schemes, including a dynamic mixing approach, to improve convergence in self-consistent iterations and reduce 3D-RISM failure rates relative to AMBER-RISM.
• File compatibility and memory management: Accepts force-field and coordinate files from AMBER and GROMACS and incorporates internal memory control mechanisms for large-scale biomolecular calculations.

Scientific Applications:

• Solvation density distributions: Calculates three-dimensional solvation density distributions around solute molecules, including complex biological entities such as protein chaperones.
• Solvent free energy calculations: Computes solvent free energies for a wide range of organic compounds using implemented free energy functionals.
• Solute–solvent interaction analysis: Enables analysis of interactions between solutes and their surrounding solvent environments in chemical and biological research.

Methodology:

Performs 3D-RISM calculations within integral equation theory, applies 22 closures and multiple free energy functionals, incorporates HI and IDC theoretical variants, and uses numerical schemes including dynamic mixing for self-consistent iteration convergence.