PC GAMESS-related discussion club

Yangsoo Kim
hit8run@gmail.com

>Re: your 1st question, only numerical frequencies are available for DFT,
Thanks. It clears out various wondering points for me.


>Re: your 2nd request
>For runtyp=hessian jobs, you can input a previous hessian with
> $force rdhess=.t. $end
I did try this option. In this case the frequencies are calculated directly from the input hessian without updating it, so that the calculation is infinitively fast but the result frequency values are not in high quality.

What I actually wanted was to do the runtype=hessian, read the initial hessian, and then update the hessian to do the normal frequency calculations like hessend=true run, hoping that separating this frequency calculation step from (runtype=optimize, hessend=true) may provide a chance to enhance the calculation speed by using analytical hessian or any other means. Of course, this is just a thought from my side, which may be useless to think of.

Thanks again for your comments,

Yang Soo