25.2.27 Keywords for Module statpt

 
$statpt
  itrvec      0
  hssupdate   bfgs
  hssfreq     0
  keeptmode   
  hssidiag    0.5
  radmax      0.3
  radmin      1.0d-4
  tradius     0.3
  threchange  1.0d-6
  thrmaxdispl 1.0d-3
  thrmaxgrad  1.0d-3
  thrrmsdispl 5.0d-4
  thrrmsgrad  5.0d-4   

Only non-default values are written in the control file except:

$statpt
  itrvec 0  

Following options are available:

itrvec

Index of the Hessian eigenvector to follow for transition structure search (transition vector). Eigenpairs are sorted in ascending order, i.e. with increasing eigenvalues and start with index 1. The eigenpairs corresponding to translations and rotations are shifted to the end. For minimization the value 0 has to be specified.

hssupdate

Method of hessian update. For minimization default is BFGS, for TS search default is Powell and none is for no update.

hssfreq

Recompute the full Hessian every N’th step during a transition state search. The default is zero and the Hessian is read in or computed in the first step only. If the standard Hessian update methods fail, it can help to use this keyword. Warning: This will make the calculation much more time demanding!

keeptmode

Freezing transition vector index.

hssidiag

diagonal hessian elements for diagonal Hessian guess (default: 0.5).

radmax

Maximum allowed value for trust radius (default: 0.3).

radmin

Minimum allowed value for trust radius (default: 1.0d-4).

tradius

Initial value for trust radius (default tradius: radmax = 0.3).

Convergence criteria

threchange

threshold for energy change (default: 1.0d-6).

thrmaxdispl

threshold for maximal displacement element (default: 1.0d-3).

thrmaxgrad

threshold for maximal gradient element (default: 1.0d-3).

thrrmsdispl

threshold for RMS of displacement (RMS = root mean square)
(default = 5.0d-4)

thrrmsgrad

threshold for RMS of gradient (default: 5.0d-4).

All values are in atomic units.