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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 78 February 20, 2026
ROKS emission energy with nonequilibrium solvent
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0 67 February 20, 2026
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1 91 February 20, 2026
Frequency calculation speedup
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1 191 February 19, 2026
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Large number of imaginary frequencies with ROKS and delta SCF
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1 82 February 19, 2026
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11 171 February 18, 2026
Q-Chem license on new MacOS
How To
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Stuck CCSD frequency calculation
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COSMO input file
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2 97 February 13, 2026
VQCCD single point calculation issue
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RIXS with TDDFT
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0 86 February 12, 2026
Wrong multiplicity for large multiplicity element when using projection based embedding
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3 97 February 12, 2026
Ground state out of equilibrium calculation
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3 161 February 11, 2026
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Questions
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Questions
1 109 February 6, 2026