Hi, I am studying the optimization of water molecule. The molecule is fragmenting in O and H2 and I want to find out whether there is any minimum of the potential at dissociation limit, i.e. what is optimum geometry at dissociation limit.
Could anyone please provide me any help in making input file for this fragment based approach.
I tried something.
%chk=frag.chk
#P B3LYP/6-31G(d,p) pop=none
Carbon dioxide fragmentation
0 1
C 0.00000000 0.00000000 -0.67798714
O 0.00000000 0.00000000 0.35131262
O 0.00000000 0.00000000 1.72929689
--Link1-- %chk=frag.chk
#P B3LYP/6-31G(d,p) guess=read geom=connectivity
#p opt freq=noraman
0 1
C 0.0 0.0 -0.67798714
O 0.0 0.0 0.35131262
O 0.0 0.0 1.72929689
-- $fragments
Frag1
1
C
--
Frag2
2-3
O
O
$end #p opt freq=noraman geom=connectivity #pfrag=(Frag1,Frag2)