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Report SCF (HF/DFT) Convergence Issues
Questions

Dear Q-Chem Community, If you have any SCF (HF/DFT) jobs that are time-consuming or are facing convergence difficulties with Q-Chem, please send them to support@q-chem.com with the subject line “SCF Convergence Issue” t…

3 1588 November 22, 2024
CDFT-CI convergence issue
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Questions
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Questions
1 141 June 24, 2026
Amber force field generation
Questions
3 182 June 23, 2026
What sort of SCF calculations are supported with external fields?
Questions
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Questions
5 221 June 15, 2026
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Questions
6 274 June 13, 2026
Lowering amplitude threshold when doing eom CCSD job
Questions
0 140 June 11, 2026
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Questions
4 401 June 7, 2026
FCIDUMP support
Questions
1 170 June 5, 2026
Upgrade to DFT-D4 in QChem 6.4
Questions
1 201 June 4, 2026
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Questions
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Questions
1 197 May 29, 2026
Simulating Vibronic and Resonance Raman Spectroscopy Using the VIBRONIC module of Q-Chem
How To
18 4528 May 25, 2026
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Questions
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Restarting finite difference frequency jobs
Questions
4 1732 May 18, 2026
“ADC(3) singlet and triplet excited states with PCM – input and disk quota issues”
Questions
4 654 May 18, 2026
aug-cc-pV5Z with external charges
Questions
3 310 May 13, 2026
CDFT block set up
How To
1 281 May 7, 2026
New basis set - excited states of Argon
Questions
3 341 May 5, 2026
PES scan not respecting mem_total
Questions
6 300 May 4, 2026
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Questions
3 398 May 3, 2026
Improving the accuracy of CPHF
Questions
1 259 May 1, 2026
TDDFT SOC results
Questions
3 405 April 28, 2026
Failure in Frequency job
Questions
3 299 April 24, 2026
Webinar 87: Improvements in the OO-DFT user interface
Webinars
0 278 April 23, 2026