ReactionMechanismGenerator / ReactionMechanismGenerator/ARC

Don't change level of theory when calculating frequency scale factors

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Module: trsh Topic: ESS Type: Bug Type: Feature Type: trsh
Dominant language
Python
Stars
51
Forks
25
Avg merge
4d 5h
Merged PRs (30d)
15

Description

Describe the bug
I was trying to calculate the frequency scale factor for wB97M-V/def2TZVP using ARC, but I noticed the following lines in the log:

The error "SCF failed" was derived from the following line in the log file:
" Q-Chem fatal error occurred in module qparser/read_rem.C, line 131:".
Troubleshooting freq job in qchem for CH2O using wB97X-D3/def2-TZVP

I don't think that ARC should be allowed to change the level of theory during this calculation, as the desired number only applies if all of the species were run at wB97M-V/def2TZVP.

Expected behavior
ARC will take troubleshooting steps if need be, but will not change the level of theory for the frequency scale factor calculation

Taking this one step further
Calculating frequency scale factors aren't the only scenario where changing the level of theory can be problematic. For example, if you want to fit BACs for a level of theory, the numbers are only good if the final opt/freq/sps were run at the desired level of theory. Should we add a feature to disable level of theory changes?

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by tracing ARC's Q-Chem frequency-scale-factor troubleshooting path, especially where the requested wB97M-V/def2TZVP level becomes wB97X-D3/def2-TZVP. Review the related calculation and troubleshooting entry points, then determine how the expected behavior should preserve the requested level and how the broader level-change option would be specified. Done means the calculation no longer silently changes level of theory, with coverage for this scenario.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
tooling
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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