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FeOs v0.9.0
FeOs v0.9.0
  • Installation
  • Help & Feedback

Python

  • Tutorials
    • Utility
      • Working with SI-units
      • On Dual Numbers in FeOs
    • Equations of state
      • Working with parameters
      • Pure substance phase diagrams
      • Entropy scaling of pure substances
      • Implementing an equation of state in python
    • Density functional theory
      • Surface tension using PC-SAFT Helmholtz energy functionals
  • Recipes
    • Critical point of a pure substance
    • Vapor pressure and boiling temperature of a pure substance
    • Phase equilibrium of a pure substance
    • Phase diagram of a pure substance
    • Phase equilibria including derivatives
    • Surface tension of a pure substance
    • Surface tension diagram of a pure substance
  • API
    • Parameter handling
      • feos.Parameters
        • feos.Parameters.__init__
        • feos.Parameters.from_json
        • feos.Parameters.from_multiple_json
        • feos.Parameters.from_records
        • feos.Parameters.new_binary
        • feos.Parameters.new_pure
        • feos.Parameters.to_json_str
      • feos.GcParameters
        • feos.GcParameters.__init__
        • feos.GcParameters.from_json_segments
        • feos.GcParameters.from_json_smiles
        • feos.GcParameters.from_segments
        • feos.GcParameters.from_smiles
      • feos.Identifier
        • feos.Identifier.__init__
      • feos.IdentifierOption
        • feos.IdentifierOption.__init__
      • feos.PureRecord
        • feos.PureRecord.__init__
        • feos.PureRecord.from_json
        • feos.PureRecord.from_json_str
        • feos.PureRecord.to_dict
        • feos.PureRecord.to_json_str
      • feos.SegmentRecord
        • feos.SegmentRecord.__init__
        • feos.SegmentRecord.from_json
        • feos.SegmentRecord.from_json_str
        • feos.SegmentRecord.to_dict
        • feos.SegmentRecord.to_json_str
      • feos.BinaryRecord
        • feos.BinaryRecord.__init__
        • feos.BinaryRecord.from_json_str
        • feos.BinaryRecord.to_dict
        • feos.BinaryRecord.to_json_str
      • feos.BinarySegmentRecord
        • feos.BinarySegmentRecord.__init__
        • feos.BinarySegmentRecord.from_json_str
        • feos.BinarySegmentRecord.to_dict
        • feos.BinarySegmentRecord.to_json_str
      • feos.ChemicalRecord
        • feos.ChemicalRecord.__init__
        • feos.ChemicalRecord.from_json
        • feos.ChemicalRecord.from_json_str
        • feos.ChemicalRecord.from_smiles
        • feos.ChemicalRecord.to_json_str
      • feos.SmartsRecord
        • feos.SmartsRecord.__init__
        • feos.SmartsRecord.from_json
        • feos.SmartsRecord.from_json_str
        • feos.SmartsRecord.to_json_str
    • Equations of state
      • feos.EquationOfState
        • feos.EquationOfState.__init__
        • feos.EquationOfState.dippr
        • feos.EquationOfState.epcsaft
        • feos.EquationOfState.gc_pcsaft
        • feos.EquationOfState.ideal_gas
        • feos.EquationOfState.joback
        • feos.EquationOfState.max_density
        • feos.EquationOfState.multiparameter
        • feos.EquationOfState.multiparameter_ideal_gas
        • feos.EquationOfState.pcsaft
        • feos.EquationOfState.peng_robinson
        • feos.EquationOfState.pets
        • feos.EquationOfState.python_ideal_gas
        • feos.EquationOfState.python_residual
        • feos.EquationOfState.saftvrmie
        • feos.EquationOfState.saftvrqmie
        • feos.EquationOfState.second_virial_coefficient
        • feos.EquationOfState.second_virial_coefficient_temperature_derivative
        • feos.EquationOfState.third_virial_coefficient
        • feos.EquationOfState.third_virial_coefficient_temperature_derivative
        • feos.EquationOfState.uvtheory
      • feos.Contributions
        • feos.Contributions.__init__
      • feos.Verbosity
        • feos.Verbosity.__init__
      • feos.State
        • feos.State.__init__
        • feos.State.chemical_potential
        • feos.State.chemical_potential_contributions
        • feos.State.compressibility
        • feos.State.critical_point
        • feos.State.critical_point_binary
        • feos.State.critical_point_pure
        • feos.State.d2p_drho2
        • feos.State.d2p_dv2
        • feos.State.dc_v_dt
        • feos.State.diffusion
        • feos.State.diffusion_reference
        • feos.State.dln_phi_dnj
        • feos.State.dln_phi_dp
        • feos.State.dln_phi_dt
        • feos.State.dmu_dni
        • feos.State.dmu_dt
        • feos.State.dp_dni
        • feos.State.dp_drho
        • feos.State.dp_dt
        • feos.State.dp_dv
        • feos.State.ds_dt
        • feos.State.enthalpy
        • feos.State.entropy
        • feos.State.gibbs_energy
        • feos.State.grueneisen_parameter
        • feos.State.helmholtz_energy
        • feos.State.henrys_law_constant
        • feos.State.henrys_law_constant_binary
        • feos.State.internal_energy
        • feos.State.is_stable
        • feos.State.isenthalpic_compressibility
        • feos.State.isentropic_compressibility
        • feos.State.isothermal_compressibility
        • feos.State.joule_thomson
        • feos.State.ln_diffusion_reduced
        • feos.State.ln_phi
        • feos.State.ln_phi_pure_liquid
        • feos.State.ln_symmetric_activity_coefficient
        • feos.State.ln_thermal_conductivity_reduced
        • feos.State.ln_viscosity_reduced
        • feos.State.mass
        • feos.State.mass_density
        • feos.State.massfracs
        • feos.State.molar_enthalpy
        • feos.State.molar_entropy
        • feos.State.molar_gibbs_energy
        • feos.State.molar_helmholtz_energy
        • feos.State.molar_internal_energy
        • feos.State.molar_isobaric_heat_capacity
        • feos.State.molar_isochoric_heat_capacity
        • feos.State.partial_molar_enthalpy
        • feos.State.partial_molar_entropy
        • feos.State.partial_molar_volume
        • feos.State.pressure
        • feos.State.pressure_contributions
        • feos.State.residual_molar_helmholtz_energy_contributions
        • feos.State.specific_enthalpy
        • feos.State.specific_entropy
        • feos.State.specific_gibbs_energy
        • feos.State.specific_helmholtz_energy
        • feos.State.specific_internal_energy
        • feos.State.specific_isobaric_heat_capacity
        • feos.State.specific_isochoric_heat_capacity
        • feos.State.speed_of_sound
        • feos.State.spinodal
        • feos.State.stability_analysis
        • feos.State.structure_factor
        • feos.State.thermal_conductivity
        • feos.State.thermal_conductivity_reference
        • feos.State.thermal_expansivity
        • feos.State.thermodynamic_factor
        • feos.State.total_mass
        • feos.State.total_molar_weight
        • feos.State.tp_flash
        • feos.State.viscosity
        • feos.State.viscosity_reference
      • feos.StateVec
        • feos.StateVec.__init__
        • feos.StateVec.molar_enthalpy
        • feos.StateVec.molar_entropy
        • feos.StateVec.specific_enthalpy
        • feos.StateVec.specific_entropy
        • feos.StateVec.to_dict
      • feos.PhaseEquilibrium
        • feos.PhaseEquilibrium.__init__
        • feos.PhaseEquilibrium.boiling_temperature
        • feos.PhaseEquilibrium.bubble_point
        • feos.PhaseEquilibrium.dew_point
        • feos.PhaseEquilibrium.heteroazeotrope
        • feos.PhaseEquilibrium.pure
        • feos.PhaseEquilibrium.tp_flash
        • feos.PhaseEquilibrium.vapor_pressure
        • feos.PhaseEquilibrium.vle_pure_comps
      • feos.PhaseDiagram
        • feos.PhaseDiagram.__init__
        • feos.PhaseDiagram.binary_vle
        • feos.PhaseDiagram.binary_vlle
        • feos.PhaseDiagram.bubble_point_line
        • feos.PhaseDiagram.dew_point_line
        • feos.PhaseDiagram.lle
        • feos.PhaseDiagram.par_pure
        • feos.PhaseDiagram.pure
        • feos.PhaseDiagram.spinodal
        • feos.PhaseDiagram.to_dict
    • Classical density functional theory
      • feos.HelmholtzEnergyFunctional
        • feos.HelmholtzEnergyFunctional.__init__
        • feos.HelmholtzEnergyFunctional.fmt
        • feos.HelmholtzEnergyFunctional.gc_pcsaft
        • feos.HelmholtzEnergyFunctional.pcsaft
        • feos.HelmholtzEnergyFunctional.pets
        • feos.HelmholtzEnergyFunctional.saftvrqmie
      • feos.PlanarInterface
        • feos.PlanarInterface.__init__
        • feos.PlanarInterface.entropy
        • feos.PlanarInterface.entropy_density
        • feos.PlanarInterface.from_density_profile
        • feos.PlanarInterface.from_pdgt
        • feos.PlanarInterface.from_tanh
        • feos.PlanarInterface.interfacial_enrichment
        • feos.PlanarInterface.interfacial_thickness
        • feos.PlanarInterface.internal_energy
        • feos.PlanarInterface.relative_adsorption
        • feos.PlanarInterface.residual
        • feos.PlanarInterface.solve
      • feos.SurfaceTensionDiagram
        • feos.SurfaceTensionDiagram.__init__
      • feos.ExternalPotential
        • feos.ExternalPotential.CustomLJ93
        • feos.ExternalPotential.CustomSteele
        • feos.ExternalPotential.DoubleWell
        • feos.ExternalPotential.FreeEnergyAveraged
        • feos.ExternalPotential.HardWall
        • feos.ExternalPotential.LJ93
        • feos.ExternalPotential.SimpleLJ93
        • feos.ExternalPotential.Steele
        • feos.ExternalPotential.__init__
      • feos.Geometry
        • feos.Geometry.__init__
      • feos.Pore1D
        • feos.Pore1D.__init__
        • feos.Pore1D.initialize
      • feos.Pore2D
        • feos.Pore2D.__init__
        • feos.Pore2D.initialize
      • feos.Pore3D
        • feos.Pore3D.__init__
        • feos.Pore3D.initialize
      • feos.Adsorption1D
        • feos.Adsorption1D.__init__
        • feos.Adsorption1D.adsorption_isotherm
        • feos.Adsorption1D.desorption_isotherm
        • feos.Adsorption1D.equilibrium_isotherm
        • feos.Adsorption1D.phase_equilibrium
      • feos.Adsorption3D
        • feos.Adsorption3D.__init__
        • feos.Adsorption3D.adsorption_isotherm
        • feos.Adsorption3D.desorption_isotherm
        • feos.Adsorption3D.equilibrium_isotherm
        • feos.Adsorption3D.phase_equilibrium
      • feos.PairCorrelation
        • feos.PairCorrelation.__init__
        • feos.PairCorrelation.entropy
        • feos.PairCorrelation.entropy_density
        • feos.PairCorrelation.internal_energy
        • feos.PairCorrelation.residual
        • feos.PairCorrelation.solve
      • feos.SolvationProfile
        • feos.SolvationProfile.__init__
        • feos.SolvationProfile.entropy
        • feos.SolvationProfile.entropy_density
        • feos.SolvationProfile.internal_energy
        • feos.SolvationProfile.residual
        • feos.SolvationProfile.solve
      • feos.FMTVersion
        • feos.FMTVersion.__init__
      • feos.DFTSolver
        • feos.DFTSolver.__init__
        • feos.DFTSolver.anderson_mixing
        • feos.DFTSolver.newton
        • feos.DFTSolver.picard_iteration
    • Automatic differentiation
      • feos.vapor_pressure_derivatives
      • feos.liquid_density_derivatives
      • feos.equilibrium_liquid_density_derivatives
      • feos.bubble_point_pressure_derivatives
      • feos.dew_point_pressure_derivatives

Rust

  • API

Theory

  • Equations of state
    • Properties
    • Stability and critical points
  • Classical density functional theory
    • Euler-Lagrange equation
    • Functional derivatives
    • DFT solvers
    • Derivatives of density profiles
    • Enthalpy of adsorption and the Clausius-Clapeyron relation
    • Ideal gas properties
    • Predictive density gradient theory
  • Models
    • Hard spheres
    • Association
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feos.State.ln_symmetric_activity_coefficient¶

State.ln_symmetric_activity_coefficient()¶

Return logarithmic symmetric activity coefficient.

Return type:

numpy.ndarray

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  • feos.State.ln_symmetric_activity_coefficient
    • State.ln_symmetric_activity_coefficient()