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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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1 316 September 28, 2026
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0 227 September 24, 2026
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0 309 September 22, 2026
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1 303 September 16, 2026
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Questions
0 305 September 2, 2026
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3 324 August 31, 2026
Spherical or Cartesian
Questions
4 360 August 26, 2026
r2scan very slow (not scf but doing extra calculations)
How To
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0 315 August 13, 2026
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1 368 August 5, 2026
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3 904 August 10, 2026
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5 931 August 10, 2026
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0 382 August 5, 2026
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Announcements
0 384 July 28, 2026
CDFT-CI convergence issue
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1 420 July 26, 2026
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1 435 July 24, 2026
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1 1079 March 12, 2023
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Questions
3 464 July 6, 2026
Calculation of transition density matrices between CVS-ADC(2)-x excited states
Questions
0 385 June 30, 2026