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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…

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What sort of SCF calculations are supported with external fields?
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How To
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Restarting finite difference frequency jobs
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Questions
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How To
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6 221 May 4, 2026
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Questions
3 304 May 3, 2026
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Questions
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TDDFT SOC results
Questions
3 318 April 28, 2026
Failure in Frequency job
Questions
3 235 April 24, 2026
Webinar 87: Improvements in the OO-DFT user interface
Webinars
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Facing convergence issue with CDFT geometry optimization
Questions
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Questions
1 214 April 22, 2026
Non-adiabatic bimolecular reaction dynamics
Questions
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Energy inconsistency with PySCF / adcc
Questions
3 320 April 17, 2026
Facing Imaginary frequency in excited state
Questions
1 249 April 17, 2026