(* Created by Wolfram Mathematica 8.0 : www.wolfram.com *)
1.0038516810866474*^-20*Sqrt[-0.00010642789797684734*Sqrt[f^(-3)] + 
   (0.000010818670519216335*(1 - Re[E^((0. + 152.01381452557615*I)*f)*
        (1 - (0. + 304.0276290511523*I)*f)*
        (1 - Erf[(8.718194036770923 + 8.718194036770923*I)*Sqrt[f]])]))/f^2]