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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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1 69 February 19, 2026
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Large number of imaginary frequencies with ROKS and delta SCF
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1 64 February 19, 2026
Ehrenfest Molecular Dynamics
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11 154 February 18, 2026
Q-Chem license on new MacOS
How To
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Stuck CCSD frequency calculation
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Wrong multiplicity for large multiplicity element when using projection based embedding
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Ground state out of equilibrium calculation
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8 282 February 9, 2026
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Questions
1 92 February 6, 2026
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Questions
2 158 January 30, 2026