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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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New basis set - excited states of Argon
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1 36 May 1, 2026
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1 79 April 22, 2026
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5 149 April 18, 2026
Energy inconsistency with PySCF / adcc
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3 130 April 17, 2026
Facing Imaginary frequency in excited state
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1 98 April 17, 2026
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3 113 April 13, 2026
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4 141 April 10, 2026
Facing large number of imaginary frequencies in LRC-wPBE functional
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3 128 April 7, 2026
Error in RI-EA-CC2 calculation
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3 154 April 5, 2026
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3 137 April 2, 2026
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3 212 March 27, 2026
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3 156 March 25, 2026
SCF convergence problem in CDFT-CI calculation
Questions
3 200 March 24, 2026
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0 141 March 17, 2026
Speeding up ADC(2) calculations
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2 190 March 17, 2026
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Questions
3 181 March 14, 2026
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4 168 March 11, 2026
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Questions
0 219 March 8, 2026
SOC for unrestricted TDDFT
Questions
3 465 March 6, 2026
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Questions
3 202 March 5, 2026