The pARTn output
Whenever the value of verbose parameter is nonzero: verbose > 0, pARTn produces several output files in a single run:
General output: artn.out
Contains the details of the current ARTn research. Depending on the value of the verbose parameter, the number of details printed differs (see verbose). For non-silent mode (verbosity>0), they are as follows.
The header contains a resume of input parameters used, written in units defined by the variable engine_units (see engine_units).
The rest of the file contains information of each step of the ARTn research, compacted into one or several lines.
Example:
istep ART_step Etot init/eign/perp/lanc/relx Ftot Fperp Fpara eigval delr npart evalf a1
[eV] -----------[eV/Ang]----------- [eV/Ang**2] [Ang]
0 Bstep void 0.0000 0 0 0 0 0 0.0133 0.0133 0.0000 0.0000 0.0000 0 1 0.00
1 Bstep/init 0.0424 1 0 4 0 0 1.1156 0.7597 0.8170 0.0000 0.1058 0 6 0.00
2 Bstep/init 0.1741 2 0 4 17 0 2.3296 1.6015 1.6919 0.5472 0.2117 1 28 0.61
3 Bstep/init 0.4006 3 0 4 14 0 3.6556 2.5399 2.6292 0.3898 0.3175 6 47 0.81
4 Bstep/init 0.7281 4 0 4 2 0 5.1192 3.6019 3.6377 0.3892 0.4234 7 54 1.00
5 Bstep/init 1.1637 5 0 4 2 0 6.7438 4.8114 4.7253 0.3881 0.5292 7 61 1.00
6 Bstep/init 1.7147 6 0 4 2 0 8.5506 6.1901 5.8988 0.3866 0.6350 7 68 1.00
7 Bstep/init 2.3885 7 0 4 2 0 10.5588 7.7569 7.1636 0.3845 0.7409 7 75 1.00
8 Bstep/init 3.1924 8 0 4 2 0 12.7850 9.5287 8.5240 0.3817 0.8468 7 82 1.00
9 Bstep/init 4.1336 9 0 4 2 0 15.2436 11.5202 9.9825 0.3780 0.9526 7 89 1.00
10 Sstep/smth 4.3998 9 1 4 17 0 15.8527 15.4459 3.5683 -0.4762 1.0037 7 111 0.23
11 Sstep/smth 4.1651 9 1 8 8 0 14.9397 14.9095 0.9502 -0.6058 0.9698 7 128 0.99
12 Sstep/eign 3.3500 9 1 12 17 0 11.2293 11.2010 0.7968 -1.0900 1.0246 7 158 0.16
13 Sstep/eign 2.2708 9 1 16 7 0 6.2064 6.0974 1.1582 -1.2398 1.0697 8 182 0.99
14 Sstep/eign 1.0081 9 1 36 9 0 1.4098 0.9444 1.0467 -1.2137 1.0057 8 228 0.95
15 Sstep/eign 1.0721 9 1 20 9 0 1.2102 0.8428 0.8685 -0.8023 1.0933 8 258 0.97
16 Sstep/eign 1.1248 9 1 22 4 0 1.0470 0.7335 0.7471 -0.9048 1.1856 8 285 1.00
17 Sstep/eign 1.0418 9 1 31 5 0 0.7919 0.5584 0.5615 -0.9824 1.2593 8 322 1.00
The columns are:
istep: iteration step of ARTn;
ART_step: computation block, possible values:Bstep/initbasin, initial pushing vector;Sstep/eignoutside of basin, pushing with eigenvector;Sstep/smthoutside of basin, push vector interpolated (smoothed);Rstep/relxunconstrained relaxation.
Etot: energy difference from initial configuration;
init/eign/perp/lanc/relx: value of iterator “iblock” for each computational block;
Ftot: the value of total force;
Fperp: value of perpendicular component of the force;
Fpara: value of the parallel component of the force;
eigval: lowest eigenvalue computed by Lanczos algorithm;
delr: the total displacement of the configuration from the initial configuration;
npart: number of paricles moved from the initial configuration;
evalf: number of force evaluations;
a1: scalar product between the current and the previous push direction.
Upon reaching different stages of the ARTn algorithm, several lines are printed indicating what happened. For example, when the algorithm has converged to a saddle point, the following is printed:
--------------------------------------------------
|> ARTn found a potential saddle point | E_saddle - E_initial = 0.98687 eV
|> Stored in Configuration Files: * Start: initp.xyz | sad0006.xyz
--------------------------------------------------
|> DEBRIEF(SADDLE) | dE= 0.98687 eV | F_{tot,para,perp}= 0.00090 0.00029 0.00086 eV/Ang | EigenVal= -0.32734 eV/Ang**2 | npart= 6. | delr= 2.72439 Ang | evalf= 809. |
--------------------------------------------------
|> Pushing forward to a minimum ***
-------------------------------------------------
Similar blocks are printed upon relaxation to the adjacent minima.
When the ARTn algorithm is finished, the finalize block is printed:
--------------------------------------------------
|> BLOCK FINALIZE..
|> number of steps: 352
|> Initial Configuration loaded...
!> CLEANING ARTn | Fail: 0
--------------------------------------------------
The integer number at Fail: 0 indicates possible failure of the research, the value 0 indicates success, while a positive value indicates the number of failed attempts.
In case of failure, there is a message containing the reason of failure, for example:
Failure message: EIGENVALUE LOST
For details on how to troubleshoot a calculation see Troubleshooting page.
In the silent mode (verbose = 0), the only information is printed at the end of ARTn algorithm, for example:
ifail: 0 * Start: initp.xyz | sad0008.xyz | min0015.xyz | min0016.xyz
which indicates the possible failure, and filenames containing the structures found by the research.
Structure files: initp.*, sad####.*, and min####.*
Contain the atomic structures found by the research, the file format .* is specified by the input variable struc_format_out (see struc_format_out):
The
initp.*contains the initial configuration, at the start of ARTn algorithm;The
sad###.*contains the saddle point found, where####are automatically assigned numbers, which are kept track in a file calledsadcounter, and increase by one for each new ARTn research.Two
min####files, containing the minima obtained by +/- relaxation from the saddle point.
Note
The structure files are only produced when the value of struc_format_out is not 'none'.
Eigenvector info: latest_eigenvec
Contains the latest eigenvector obtained by Lanczos procedure. This can be useful when restarting a calculation with a prescribed initial eigenvector (see eigenvec_guess).
Restart file: artn.restart
Contains the needed information for pARTn to resume an aborted calculation (see lrestart).