!Physical and mathematical constants
module constantParameters
  implicit none

  public

  integer,  parameter:: dp    = kind(0.d0)          ! Precision
  real(dp), parameter:: PI    = 4.0_dp*ATAN(1.0_dp) ! Number pi
  real(dp), parameter:: qe    = 1.60217662e-19_dp   ! Elementary charge
  real(dp), parameter:: kb    = 1.38064852e-23_dp   ! Boltzmann constants SI
  real(dp), parameter:: eV2J  = qe                  ! Electron volt to Joule conversion
  real(dp), parameter:: eps_0 = 8.8542e-12_dp       ! Epsilon_0

  real(dp), parameter:: eV_to_K   = 11604.5_dp ! Convert eV to K
  real(dp), parameter:: cm3_to_m3 = 1.0e6_dp   ! Convert cm^-3 to m^-3

end module constantParameters