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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 1531 November 22, 2024
Unexpected Energy Ordering in TDDFT Nonequilibrium PCM
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Amber force field generation
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What sort of SCF calculations are supported with external fields?
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Questions
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4 331 June 7, 2026
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0 124 June 2, 2026
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Questions
1 125 May 29, 2026
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How To
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Questions
1 675 May 22, 2026
Restarting finite difference frequency jobs
Questions
4 1676 May 18, 2026
“ADC(3) singlet and triplet excited states with PCM – input and disk quota issues”
Questions
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Questions
3 236 May 13, 2026
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How To
1 206 May 7, 2026
New basis set - excited states of Argon
Questions
3 257 May 5, 2026
PES scan not respecting mem_total
Questions
6 228 May 4, 2026
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Questions
3 306 May 3, 2026
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Questions
1 202 May 1, 2026
TDDFT SOC results
Questions
3 323 April 28, 2026
Failure in Frequency job
Questions
3 239 April 24, 2026
Webinar 87: Improvements in the OO-DFT user interface
Webinars
0 224 April 23, 2026
Facing convergence issue with CDFT geometry optimization
Questions
1 226 April 22, 2026
Loading basis set from file?
Questions
1 218 April 22, 2026
Non-adiabatic bimolecular reaction dynamics
Questions
5 325 April 18, 2026
Energy inconsistency with PySCF / adcc
Questions
3 324 April 17, 2026
Facing Imaginary frequency in excited state
Questions
1 252 April 17, 2026