## Firefly and PC GAMESS-related discussion club

Learn how to ask questions correctly

** Re: Problems with hessian **
Masoud Nahali

masoudnahali@gmail.com

Dear GuilhermeIs one of the frequencies too small ? If so please double the number of displacements in each direction to see whether the smaller frequency disappears or not. You can apply it using $FORCE NVIB=2 $END. Then please let us know whether it improves the results. If the issue doesn't fit the proposed solution please let us see the output file.

Sincerely Yours, m

-------------

Masoud Nahali

SUT

On Sat Nov 30 '13 10:47pm, guilherme wrote

------------------------------------------

>Hi guys,

>I have a problem with the calculate of the hessian. I cannot achieve the correct conformation of my transition state. The calculate ends "normally" but it shows the message:

>THIS IS NOT A STATIONARY POINT ON THE MOLECULAR PES *

>* THE VIBRATIONAL ANALYSIS IS NOT VALID !!!

>and in the result I had to find just one negative frequency but in this case found 2 negative frequencies.

>

>

>My input is:

> $contrl runtyp=hessian coord=zmt nzvar= 39 $end

> $basis gbasis=N311 ngauss=6 ndfunc=1 npfunc=1 nffunc=1 $end

> $contrl icut=11 itol=30 maxit=5000 $end

> $statpt hssend=.t. nstep=1000 dxmax=0.1 trupd=.f. $end

> $data

>I've already tried to freeze the important bonds but didn't work too.

>Please guys, does someone have an idea?

>

Sat Nov 30 '13 11:25pm

This message read **595** times