Hi Juan, Have you tried a QST3? In addition to the
reactants and products, this will allow you to use input an initial guess for
the transition state.
Additionally, you could get an estimate of the
reaction path using opt=path from the optimized reactant. The highest energy
point along the path can be used as an estimate for the transition state of the
QST3 calc, while the step down the gradient on the reactant side may be used as
the reactant guess in the QST3, and so on for the product.
Whichever
method you use, I would run an IRC once you are finished to ensure the
transition state you've calculated is the for the reaction you intended.
Good luck,
Amy
From:
Juan Manuel mayerzmytm#%#gmail.com <owner-chemistry-#-ccl.net>
To: "Austin, Amy J "
<amy_jean_austin-#-yahoo.com>
Sent: Monday, July 15, 2013 12:13 PM
Subject: CCL:G: Finding the transition
state
Hello Ailar,
I have not a
lot of experience working with theoretical methods, but something that worked to
me in order to find transition structure is use the berny method (only TS
initial guess needed) with the keyword NoEigenTest, otherwise I found this
process very dificult
opt=(ts,noeigentest).......
best
Juan
Manuel Arce