Question about Fe FS potential

Dear Professor
I want to generate a potential file (setfl style) with the parameters from the paper in 2004,
“G.J. Ackland, M.I. Mendelev, D.J. Srolovitz, S. Han and A.V. Barashev, J. Phys.: Condens. Matter 16, S2629-S2642 (2004).”
but then I met some troubles .

The pair potential I get from my code is different from the potential file in LAMMPS in which the 1st~937th value are 1.0E+12, while my values are about 1.7E+7(r is about 5.08E-4 A)…From the expression I think the type of the value must be float rather than int. So would u please explain this to me. Is there some mistakes during my calculation or my understanding for LAMMPS? Thank U very much, and wish Professor happy everyday!
,

and my code is listed below

double CEAMFS::GetFPhi(double r)
{
double phi1;

double rs = 0.4683766/(pow(26.0,2.0/3.0)2);
double x = r/rs;
double kexi = 0.1818
exp(-3.2x) + 0.5099exp(-0.9423x) +
0.2802
exp(-0.4029x) + 0.02817exp(-0.2016*x);
phi1 = 9734.2365892908 * kexi * FH(1.0-r);
phi1 = kexi * FH(1.0-r);

return phi1;
}