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GENERAL_REACTION

Specifies parameters for general forward/reverse kinetic reaction.

Required Cards:

REACTION <string>
Reaction equation. The forward rate is applied to the reaction quotient of species on the left side of the reaction. The reverse or backward rate is applied to the right side.

Optional Cards:

FORWARD_RATE <float>
Rate constant for nth-order forward reaction [kg-water(n-1)/mol(n-1) -sec]
BACKWARD_RATE <float>
Rate constant for nth-order reverse reaction [kg-water(n-1)/mol(n-1) -sec]

Examples:

GENERAL_REACTION
  REACTION Tracer <-> Tracer2
  FORWARD_RATE 1.7584d-7 ! half life at 0.125 y
  BACKWARD_RATE 0.d0
/
CHEMISTRY
  PRIMARY_SPECIES
    A(aq)
    B(aq)
    C(aq)
  /
  ...
  GENERAL_REACTION
    REACTION A(aq) <-> B(aq)
    ! Calculating forward rate from half-life
    ! forward rate = -ln(0.5) / half-life [1/sec]
    FORWARD_RATE 1.75836d-9  ! 1/s  half life = 12.5 yrs
    BACKWARD_RATE 0.d0
  /
  GENERAL_REACTION
    REACTION B(aq) <-> C(aq)
    FORWARD_RATE 8.7918d-10  ! 1/s  half life = 25. yrs
    BACKWARD_RATE 0.d0
  /
  GENERAL_REACTION
    ! Note that C(aq) simply decays with no daugher products
    REACTION C(aq) <->
    FORWARD_RATE 4.3959d-9  ! 1/s  half life = 5. yrs
    BACKWARD_RATE 0.d0
  /
  ...
/