Given a kinetic rate at a reference temperature (argument tkref) this function calculates its temperature-scaling factor following Arrhenius kinetics.

ftemp_arrh(tk, dha, tkref = 298.15)

Arguments

tk

Temperature (Kelvin)

dha

Activation energy (J mol-1)

tkref

Reference temperature (Kelvin)

Value

A numeric value for \(f\)

Details

To correct for effects by temperature following Arrhenius kinetics, and given a reference temperature \(T_0\), \(f\) calculates the temperature scaling. Arrhenius kinetics are described by an equation of form \(x(T)= exp(c - \Delta H_a / (T R))\). The temperature-correction function \(f(T, \Delta H_a)\) is thus given by \(f=x(T)/x(T_0)\) which is: $$ f = exp( \Delta H_a (T - T_0) / (T_0 R T_K) ) $$ \(\Delta H_a\) is given by argument dha. \(T\) is given by argument tk and has to be provided in Kelvin. \(R\) is the universal gas constant and is 8.3145 J mol-1 K-1. Note that this is equivalent to $$ f = exp( (\Delta H_a/R) (1/T_0 - 1/T) ) $$

Examples

# Relative rate change from 25 to 10 degrees Celsius (percent change) print( (1.0-ftemp_arrh( 283.15, 100000, tkref = 298.15))*100 )
#> [1] 88.19912