## NEB

This keyword controls the NEB search of transition states. If no option, a default calculation was made (NEB PTITR=13 OPT=COMB TYPROT=SVD NODEBUG).

PTITR=

Number of intermediate image in NEB strings between initial points

PTMAX=

Maximum number of image for NEB, at the end of FIRE OPTIMIZATION if this number is not reach, add two new images around each maximum and make a new OPTIMIZATION.

TYPROT=

Specify the type of rotation (SVD only at the moment)

TYPROT

Perform rotation of images to match with each others at each step of NEB. It takes default rotation to position the 3 first atoms allways in the same plan.

KNEB=

Set de spring constant. Default is 0.0972 Hartree/Bohr

NDEBUG=

For NEB. Write information in debug files and set interval.

NODEBUG

For NEB. No information file.

OPT=

Select one of the 3 types of NEB OPTIMIZATION of standard NEB (OPT=GRAD, FIRE, COMB(FIRE+GRAD)). OPT=DELR skip standard NEB, in TSNEB= (mandatory in this case) create a new rope with TS fixed point

FTOL=

Optimization energetic convergence criterion for the OPT FIRE. Default is 5.10E-3 Hartree.

MAX=

It corresponds to maximum displacement for FIRE search (default is 0.188 Bohr)

GRADTOL=

It corresponds to the gradient convergency criterion (default = 1e-3 Hartree).

TOLITER=

Set convergence threshold for OPT Gradient (default is 1E-6)

STEP=

The default is 100. Number of maximal steps for gradient convergency below thresholdTSOPT=

Same as TSOPT followed with a NEB optimization select one of the 3 types of NEB OPTIMIZATION implemented (TSOPT=GRAD, FIRE, COMB(FIRE+GRAD)

TSOPT

Optimize the different transistion states using frequency analysis (following one negative frequency)

TSTOL=

In the case of TSOPT it corresponds to the gradient criterion to converge the transition state (default = 1E-5 Hartree).

DUPDWN=

In the case of TSOPT,to help the minmax TS optimizationi, one freeze one direction optimization if the gradoents become too differents. Default criterion ratio is 2.5.

FIFTOL=

Optimization convergence criterion for the TSOPT FIRE. Default is 1.10E-4 Hartree.

FIGRDTOL=

In the case of TSOPT it corresponds to the gradient criterion (default = 5E-5 Hartree).

FITER=

Set convergence threshold for TSOPT Gradient (default is 1E-8)