[gmx-users] second derivative of force

[Mark Abraham]

Nguyen Hoang Phuong wrote:
> 
> Hi,
> 
> thanks Mark for the suggestion. I made an mistake in writing the first 
> email. Actually, I need the first derivative of force, i.e, the second 
> derivative of total energy.
> 
> Perhaps, a modification the code that computes the Hessian is a good 
> idea. To do this, does anyone know exactly where is the code such that I 
> just add the if command
> 
> if(i==j){
> 
> ...calculating the Hessian
> 
> }

grep essian $GROMACS_DIR/src/*/*.[ch]

Mark