CCL:G: What to change in gaussian03 to calculate thermochemistry?

 Sent to CCL by: Steve Williams [willsd .]
I looked at the output file you posted; I suspect there may be a bug in the G03 version you are using. There is nothing wrong with your input; your optimization converged and the subsequent frequency calculation properly read the converged wavefunction from the checkpoint file written in the last step of the optimization. BUT the frequency calculation could not converge the scf equations using this already converged wavefunction as the guess! This cannot be proper behavior. I am not sure about other scf convergers with semi-empirical methods, but you might try this... Copy the route line from the failed freq calculation, keep the same checkpoint file from the optimization, and add scf=qc to the new route line. Your new input file will not need the geometry (it will be read
from the checkpoint), but you will need the 1 2 to set the charge and
 multiplicity of your radical cation.
 Steve Williams
 taye beyene demisse wrote:
 Sent to CCL by: "taye beyene demisse" [sene3095 ~]
 Sent to CCL by: "Taye Beyene Demisse" [sene3095[a]]
Dear CCL subscribers, I am doing a research on conducting polymers(Theoretical and experimnetal investigation. While I am calculating the theormodynamic properties by Gaussian03 package it is reporting error. you may have used the program ,so please look at my result at the folowing link, and suggest me some correcting methods.(Copy and paste the link to view the result)
 Thank you,
 Taye Beyene(AAU)>