UT theoretical chemistry code forum

Thanks for reporting the bug. The corrected version has been updated in CVS.

Despite the correction to the vproj function there is no dneb improvement in the pt111 benchmark system described in the Sheppard (JCP) 2008 paper.

The script has been checked and can handle non-orthogonal cells at this point.

For a hard to converge paths I would pre-converge using quick-min (QM) as opposed to FIRE. FIRE tends to be more aggressive and will sometimes blow past a minimum into a separate basin. You should always use LCLIMB = .TRUE. * unless for some reason you really don't want to know the saddle exactly (a...

It looks to me like you are entering the data correctly. If you have four atom groups in your CHGCAR then you need to enter four numbers, separated by spaces and <enter>. If you have not updated on cvs in a while that particular script was updated in late August.

The optimizers are incorporated in into our latest VTST package. The flags for using these optimizers can be found at: http://theory.cm.utexas.edu/vtsttools/optimizers/ When using the IOPT flag you must set IBRION=3 and POTIM=0.0 to disable the optimizers intrinsic to VASP.

I would suggest that you try the lbfgs optimizer. IBRION=3 POTIM=0.0 IOPT=1 LGLOBAL=.TRUE INVCURV=0.05 For a system with strong bonds like oxygen-oxygen you will have to reduce the initial scaling of the inverse hessian (INVCURV parameter) to a more conservative value ~0.01 You can find details abou...

When you set (EDIFFG = -.1E-1) in the INCAR this means that the NEB will converge when the maximum Fneb (force with neb projections and spring forces) in any direction falls below that threshold of 0.01 eV/Ang The line in the OUTCAR that can be used to monitor this convergence is: FORCES: max atom, ...

The idea behind Gman is to give us a place to test new code and new ideas on empirical potentials without the overhead of the DFT. Some of the advantages of Gman and the use of python gives us is the ability to run programs interactively and more options as far as visualization is concerned. Gman is...

The harmonic prefactor looks like this: v = Prod (vmin_i) /Prod (vsaddle_j) where (vmin) is the normal modes at the minimum and i goes from i=1->3N and (vsaddle) is the normal modes at the saddle and j goes from j=1->3N-1 The one imaginary mode at the saddle is not left out of the product N is the n...