Posted by Björn Roos on June 02, 2004 at 08:03:42:
In Reply to: Re: CASPT2 analytic gradient was so bad??? posted by Evgeny K. Dolgov on May 17, 2004 at 13:41:16:
I cannot se any problem here. For such small molecules as formaldehude and acetaldehyde one can certainly vary some degress of freedom while others are optimized, using only energies and possibly numerical gradients. For example: for each out of plane bending angle you optimize everything else (three other degrees of freedom if you keep C_s symmetry).