Given the molar masses and polarities of two compounds, as well as the operation temperature and pressure, calculates the diffusivity coefficient by the Brokaw's equation:
$$ Dab = \frac{1.858.10^{-3}.T^\frac{3}{2}.{(\frac{1}{Ma}+\frac{1}{Mb})}^{\frac{1}{2}}}{PΩdσab^2}; $$
Been:
The Brokaw's equation uses the Hirschfelder's equation with alteration in the colision diameter and the colision integral:
$$ Ω_D = Ω^D + \frac{0,196.S{AB}^2}{T^} $$
$$ σ_{AB} = {σ_A.σ_B}^{\frac{1}{2}} $$