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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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Energy inconsistency with PySCF / adcc
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3 45 April 13, 2026
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1 64 April 7, 2026
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3 88 April 5, 2026
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2 109 April 1, 2026
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3 138 March 27, 2026
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3 103 March 25, 2026
SCF convergence problem in CDFT-CI calculation
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3 127 March 24, 2026
Strange outcome in RAS-SF calculation
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0 91 March 17, 2026
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2 135 March 17, 2026
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3 126 March 14, 2026
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4 116 March 11, 2026
MRSF: differences between Q-Chem and OpenQP
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0 149 March 8, 2026
SOC for unrestricted TDDFT
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3 372 March 6, 2026
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3 142 March 5, 2026
Resolution of identity for CDFT?
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6 176 March 3, 2026
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4 196 February 28, 2026
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3 534 February 28, 2026
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3 142 February 26, 2026
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1 169 February 25, 2026
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8 192 February 24, 2026
Normal Modes Question
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3 349 February 23, 2026
Symmetry in CCSD(T) frequency calculation
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4 201 February 23, 2026
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1 187 February 21, 2026
Units of vibrational eigenvectors
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2 229 February 20, 2026
EOM-EA-CCSD on a Excited state
Questions
1 153 February 20, 2026