Artificial Force Induced Reaction(AFIR) Method :
Reaction proceses from A and B into AB can be searched very rapidly!
AFIR(Aritificail Force Induced Reaction) :
Explore reaction processes by pressing reactants mutually
In the most recent version of GRRM program (GRRM14) a new technique (Aritificial Force Induced Reaction method: AFIR)
to search reaction proceses from A and B into AB has been introduced.
This method is especially effective to intermolecular reaction processes, which have been very diffcult to be searched by the ADD-following method.As shown in the left figure above, artificial binding forces are applied between A and B. Additional of an energy term proportional to the distance between A and B rAB brings the potential into the lower curve shown in the right figure above, and then the no barrier curve enforces A and B into AB smoothly. This is equivalent to application of artificial attractive forces to bind A and B very rapidly.
Such an artificial process is not a real process, but removal of the artificial forces easily lead to the real process. The reaction pathway with a barrier (TS) on the real potential surface can easily be obtained. This method enables us to search binding reactions between molecules very rapidly, which have been difficult to find out by the ADD-following method.
Although only two reactants A and B are involved in the above figure, the AFIR method can be used for many reactants, three or the more.