OPTGEOM for RUNCONFS
- 
Hello!
Help with the problem! When you try to run geometry optimization for configurations, only the geometry optimization of the original connection is started. I am attaching a view of a part of the input file, as it is all set.CRYSTAL
0 0 0
194
3.065 17.656
4
22 0 0 0.5
14 0 0 0.75
22 0.666666 0.333333 0.364919
6 0.333333 0.666666 0.427507
SCELCONF
1 0 0
0 1 0
0 0 1
RUNCONFS
ATOMSUBS
22 273
END
OPTGEOM
MAXCYCLE
500
END
END - 
Hi,
Before running the actual single-point or geometry optimization calculations on the configurations with RUNCONFS, a list of configurations needs to be generated by use of the CONFRAND option. The list of generated configurations is saved into a file CONFIGURATIONS.DAT that is then read by the next RUNCONFS calculation.
Let us go through this step-by-step. I take your system as an example.
- First, you would setup an input for the CONFRAND calculation. For instance:
 
Title CRYSTAL 0 0 0 194 3.065 17.656 4 22 0 0 0.5 14 0 0 0.75 22 0.666666 0.333333 0.364919 6 0.333333 0.666666 0.427507 SCELCONF 1 0 0 0 1 0 0 0 1 CONFRAND 1 5 2 ENDHere I am selecting just one crystallographic site for substitution, specified by atom number 5, which is a Ti atom. Given the symmetry of this system, that atom has a multiplicity of 4 (i.e. there are other 3 Ti atoms symmetry-related to it). This can be inspected from here (in bold the selected atoms, in italic its symmetry-equivalents):
N. ATOM EQUIV AT. N. X Y Z 1 1 1 22 TI 0.00000000000E+00 0.00000000000E+00 -5.00000000000E-01 2 1 2 22 TI 0.00000000000E+00 0.00000000000E+00 0.00000000000E+00 3 2 1 14 SI 0.00000000000E+00 0.00000000000E+00 -2.50000000000E-01 4 2 2 14 SI 0.00000000000E+00 0.00000000000E+00 2.50000000000E-01 **5 3 1 22 TI -3.33334000000E-01 3.33333000000E-01 3.64919000000E-01** *6 3 2 22 TI 3.33334000000E-01 -3.33333000000E-01 -1.35081000000E-01 7 3 3 22 TI 3.33333000000E-01 -3.33333000000E-01 -3.64919000000E-01 8 3 4 22 TI -3.33333000000E-01 3.33334000000E-01 1.35081000000E-01* 9 4 1 6 C 3.33333000000E-01 -3.33334000000E-01 4.27507000000E-01 10 4 2 6 C -3.33333000000E-01 3.33334000000E-01 -7.24930000000E-02 11 4 3 6 C -3.33333000000E-01 3.33334000000E-01 -4.27507000000E-01 12 4 4 6 C 3.33334000000E-01 -3.33333000000E-01 7.24930000000E-02The last input parameter of CONFRAND, which I set to 2, determines how many of these 4 Ti atoms will be substituted.
- By running it you get the following output:
 
******************************************************************************* SUBSTITUTIONS AT SITES (LABELS) : 5 7 6 8 ********************************** COMPOSITION : 2 / 4 ********************************** NUMBER OF SIC : 3 ******************************************************************************* ---> 1 SIC FOUND AT TRY 1 - CONFIGURATION 0 0 1 1 MULTIPLICITY 2 - RANK 1 - CANONICAL RANK 1 ---> 2 SIC FOUND AT TRY 2 - CONFIGURATION 1 0 1 0 MULTIPLICITY 2 - RANK 5 - CANONICAL RANK 2 ---> 3 SIC FOUND AT TRY 4 - CONFIGURATION 1 0 0 1 MULTIPLICITY 2 - RANK 3 - CANONICAL RANK 4 ******************************************************************************* 3 SIC FOUND AFTER 4 TRIES *******************************************************************************that is 3 symmetry-independent configurations (SICs) are found and stored in the external file CONFIGURATIONS.DAT.
- At this point you are ready to run a RUNCONFS calculation (note that the CONFIGURATIONS.DAT file generated at the previous step needs to be placed inside the scratch folder of the new job). For instance with:
 
Title CRYSTAL 0 0 0 194 3.065 17.656 4 22 0 0 0.5 14 0 0 0.75 22 0.666666 0.333333 0.364919 6 0.333333 0.666666 0.427507 SCELCONF 1 0 0 0 1 0 0 0 1 RUNCONFS ATOMSUBS 22 273 ENDIn this case I ask to substitute Ti with Ta.
Hope this helps,