Sandia National Laboratories Tramonto

Charged Systems: Dielectric Constant Parameters

These parameters detail the treatment of the dielectric constant parameters when Type_coul is turned on, and Poisson's equation is to be solved.

  • Type_dielec(int): Flag for the treatment of dielectric constants. Options are:
    • 0: uniform dielectric constant everywhere in the domain.
    • 1: set different dielectric constants for fluid regions and surface regions in the computational domain.
    • 2: set different dielectric constants for bulk fluid, restricted fluid (i.e. in a pore), and surfacece regions in the computational domain.
    • 3: set a constant dielectric constant in a surface, but allow variation with density in the fluid (for use with Type_coul=3 option).
  • Dielec_bulk(real): The dielectric constant of the bulk fluid. If Dielec_ref<0, enter the ratio of the dielectric constant in the bulk fluid relative to a default reference value of 78.5. If Dielec_ref>0, enter the dielectric constant, and the code will compute Dielec/Dielec_ref.
  • Dielec_pore(real): The dielectric constant for a "restricted" fluid (e.g. a fluid confined in a pore). Again enter ratio relative to default reference value of 78.5 unless Dielec_ref>0.
  • Dielec_X(real): The distance from the surfaces where the fluid will be considered to be restricted by a surface, and where Dielec_pore will be used.
  • Dielec_wall[Nwall_type](real vector): The the dielectric constant to be used inside the surfaces in the system. Note that different surface types may be assigned different dielectric constants. Again enter the parameter as a ratio relative to a default reference value of 78.5 unless Dielec_ref>0.