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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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1 309 September 28, 2026
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0 221 September 24, 2026
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0 305 September 22, 2026
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1 286 September 16, 2026
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Questions
0 298 September 2, 2026
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3 316 August 31, 2026
Spherical or Cartesian
Questions
4 348 August 26, 2026
r2scan very slow (not scf but doing extra calculations)
How To
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1 289 August 17, 2026
Q-Chem Webinar 89: M-Chem
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0 308 August 13, 2026
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1 359 August 5, 2026
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Questions
3 893 August 10, 2026
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5 922 August 10, 2026
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0 373 August 5, 2026
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Announcements
0 377 July 28, 2026
CDFT-CI convergence issue
Questions
1 414 July 26, 2026
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1 432 July 24, 2026
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1 1074 March 12, 2023
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Questions
3 455 July 6, 2026
Calculation of transition density matrices between CVS-ADC(2)-x excited states
Questions
0 380 June 30, 2026