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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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How To
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Is it possible to use the NTO-rotated orbitals (for a specific TDDFT state) as the MO set in a subsequent Q-Chem job?
Questions
4 66 January 4, 2026
Conceptual question regarding the applicability of SF-TDDFT method
Questions
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How To
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Questions
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Questions
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3 70 December 23, 2025
Basis set compatibility issue
Questions
3 108 December 23, 2025
IEF-PCM for SMD olvation model
Questions
1 74 December 18, 2025
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Questions
5 113 December 18, 2025
downloading and installing qcIntel version 6402
Questions
1 87 December 17, 2025
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Questions
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Questions
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Questions
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Questions
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Questions
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Questions
15 221 November 27, 2025
neo-scf calculations
Questions
1 96 November 25, 2025
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Questions
1 109 November 25, 2025
Cannot get rid of Imaginary Frequency
Questions
3 170 November 25, 2025
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Questions
11 218 November 24, 2025
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Questions
3 384 November 21, 2025
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How To
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Questions
1 141 November 20, 2025
Webinar 83: Coupled Cluster Developments in Q-Chem
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Questions
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