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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 1396 November 22, 2024
Failure in Frequency job
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Webinar 87: Improvements in the OO-DFT user interface
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1 35 April 22, 2026
TDDFT SOC results
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0 37 April 22, 2026
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1 47 April 22, 2026
Non-adiabatic bimolecular reaction dynamics
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5 112 April 18, 2026
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3 100 April 17, 2026
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1 68 April 17, 2026
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3 90 April 13, 2026
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4 113 April 10, 2026
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3 94 April 7, 2026
Error in RI-EA-CC2 calculation
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3 119 April 5, 2026
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3 109 April 2, 2026
IRC calculation issue
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2 142 April 1, 2026
NAC calculation
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3 169 March 27, 2026
How to generate FCIDump file
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3 134 March 25, 2026
SCF convergence problem in CDFT-CI calculation
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3 167 March 24, 2026
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0 117 March 17, 2026
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2 160 March 17, 2026
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3 156 March 14, 2026
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0 181 March 8, 2026
SOC for unrestricted TDDFT
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3 425 March 6, 2026
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3 174 March 5, 2026
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6 209 March 3, 2026
ROHF energy discrepancy between Q-Chem and CFOUR
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4 231 February 28, 2026
Optimal settings for large DFT calculations
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3 556 February 28, 2026
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Questions
1 201 February 25, 2026