Molcas Forum

jiang663

Member

Registered: 2022-03-01

Posts: 5

About scanning in different coordinate and file saving

Hi, I just have a question about scanning coordinate. In this example, it does a "relaxed" scan:

> FOREACH D in (60,62,64,66)
&GATEWAY
  ...
  Constraints
    d = Dihedral C1 N2 N3 C4
   Values
    d = $D
  End of Constraints

  > DO WHILE
    &SEWARD
    &SCF
    &SLAPAF
  > END DO
> END FOREACH

If I remove the while loop, does that mean I have done a rigid scan? (I previously asked question about scan (https://molcasforum.univie.ac.at/viewtopic.php?id=849) and I get reply that it is not possible to do rigid scan, but I didn't understand why)

Also, during the function, the different outreach calculation overwrite the former one (e.g. one single molden file will be output since former files with different value are overwritten) I tried to set up $MOLCAS_SAVE as:

>>> FOREACH D IN (2.2,3.2,4.2)

>>> EXPORT MOLCAS_SAVE = pyrrole_$D

...

>>> END FOREACH

However, it still overwrite the file for different D value. Do you know how to save different file for single input file?

Last edited by jiang663 (2022-06-14 02:54:00)

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,204

Re: About scanning in different coordinate and file saving

If I remove the while loop, does that mean I have done a rigid scan? (I previously asked question about scan (https://molcasforum.univie.ac.at/viewtopic.php?id=849) and I get reply that it is not possible to do rigid scan, but I didn't understand why)

No, it won't, it will just perform 4 identical single-point calculations. The reason is that the constraints block does not change the geometry, only SLAPAF does, and does it in a "little by little" way, trying to minimize the energy at the same time as fulfilling the constraints.

Do you know how to save different file for single input file?

MOLCAS_SAVE only takes the values INCR or ORIG (or unset), see https://molcas.gitlab.io/OpenMolcas/sph … -variables. You could try MOLCAS_SAVE=INCR, or setting MOLCAS_OUTPUT instead (not 100% sure it will work), or manually copy the file(s) you want, e.g.

  > END DO
  > COPY $Project.Opt.xyz pyrrole_$D.Opt.xyz
> END FOREACH