If you have problems during the execution of MRCC, please attach the output with an adequate description of your case as well as the followings:
  • the way mrcc was invoked
  • the way build.mrcc was invoked
  • the output of build.mrcc
  • compiler version (for example: ifort -V, gfortran -v)
  • blas/lapack versions
  • as well as gcc and glibc versions

This information really helps us during troubleshooting :)

LNO-CCSD(T) calculation converged to wrong HF energy (def2-qzvpp basis)

  • eszter.makkos
  • Topic Author
  • Offline
  • New Member
  • New Member
More
1 month 1 day ago #1460 by eszter.makkos
Dear MRCC support,I recently ran a series of LNO-CCSD(T) calculations on systems containing a ferrocene group and potentially an additional Ni or Pd atom. The only auxiliary basis set available for Fe, Ni and Pd atoms is the def2-qzvpp. (def2-qzvpp-ri and def2-qzvpp-ri-jk).Most of the calculations had problems with the HF converge, i.e. the energy converged to a higher value than it was obtained in the first or second iteration step. A fewer of them converged correctly (compared to what we expect based on DFT results)I attached a successful and a “failed” case to my topic entry with the complete output folder.I have also noticed that the aug-cc-pvtz basis set in a simple HF calculation converged to the right energy for one structure that I tested on, but then I could not read in the SCFDENISTIES properly to use it as an initial SCF guess for the LNO-CCSD(T) job.Therefore, I would like to ask if there is a way to avoid this convergence failure by using an additional parameter, apply a better SCF guess, or a different basis set or by any other possible solution.Thank you for your help,Eszter

Please Log in or Create an account to join the conversation.

  • kallay
  • Offline
  • Administrator
  • Administrator
  • Mihaly Kallay
More
4 weeks 1 day ago #1461 by kallay
Dear Eszter,
Could you also post the relevant output files?

Best regards,
Mihaly Kallay

Please Log in or Create an account to join the conversation.

  • eszter.makkos
  • Topic Author
  • Offline
  • New Member
  • New Member
More
4 weeks 1 day ago #1462 by eszter.makkos
Excuse me, I was supposed to attach the following files to my previous entry:This is the output file which converged to the wrong HF energy:

 

File Attachment:

File Name: failed_Fc_...2.tar.gz
File Size:79 KB

 And this is the one that worked: 

File Attachment:

File Name: worked_Fc_...d.tar.gz
File Size:49 KB
Thank you for your response,Eszter

Please Log in or Create an account to join the conversation.

  • kallay
  • Offline
  • Administrator
  • Administrator
  • Mihaly Kallay
More
4 weeks 21 hours ago #1463 by kallay
Dear Eszter,
The best solution is to restart the HF from the density evaluated with the def2-SVP basis set. To that end, you need:
calc=LNO-CCSD(T)
basis=def2-qzvpp
scfiguess=small
basis_sm=def2-SVP
 

Best regards,
Mihaly Kallay

Please Log in or Create an account to join the conversation.

  • eszter.makkos
  • Topic Author
  • Offline
  • New Member
  • New Member
More
6 days 20 hours ago #1466 by eszter.makkos
Thank you for your answer, indeed this solved the convergence problem.

Best wishes,
Eszter

 

Please Log in or Create an account to join the conversation.

Time to create page: 0.042 seconds
Powered by Kunena Forum