vdw_gaussian_set Subroutine

private subroutine vdw_gaussian_set(params, A, B, rcut)

Setter for gaussian interaction. The potential is truncated and force-shifted.

The potential U is given by:

   V = A*exp(-B*r^2)  
   U = V - V(rcut) - (r - rcut)*dV/dr, r < rcut  
       0, r >= rcut,

where dV/dr is evaluated at r = rcut.

User-set parameters:

• params(1) = A
• params(2) = B
• params(3) = rcut

Internally stored parameters:

• params(4) = V(rcut)
• params(5) = dV/dr(rcut)

Arguments