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Rate constant

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DESCRIPTION

For a given reaction mechanism, the rate constant K can be expressed in terms of a power-law relationship (P) and an Arrhenius-type relationship (A) involving the absolute temperature T as follows :
  K(T) = prefac*P(T)*A(T)

where    P(T) = ((Ta+T)/(Ta+Tr))**beta
              A(T) = exp(-Ea/R*(1/(Ta+T)-1/(Ta+Tr))

   OPTIONS
 
-1 
 Upper level menu
1 
 Modification of Ta
Allows to define a shift in temperature. The shift must be set with respect to the absolute scale. Default value : 0.d0
2 
 Modification of Tr
Allows to define a reference temperature. Default value : 298.15d0, that is, room temperature if absolute temperature is used. At reference temperature, both expressions P(T) and A(T) reduce to 1.
3 
 Modification of prefac
Allows to define/modify the pre-exponential factor. With the exception of transient problems, evolution is highly recommended. Default value : 1.d0
4 
 Modification of beta
Allows to define/modify the temperature exponent. Default value : 0.d0
5 
 Modification of Ea/R
Allows to define/modify the ratio of the activation energy to the molar gas constant. Default value : 0.d0
6 
 Modification of entalp
Allows to define/modify the enthalpy. For use in the energy equation. An exothermic (resp. endothermic) reaction gives rise to a positive (resp. negative) value of the enthalpy. Default value : 0.d0
SEE ALSO