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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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1 311 September 28, 2026
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0 224 September 24, 2026
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0 307 September 22, 2026
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1 288 September 16, 2026
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Questions
0 300 September 2, 2026
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3 318 August 31, 2026
Spherical or Cartesian
Questions
4 353 August 26, 2026
r2scan very slow (not scf but doing extra calculations)
How To
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1 302 August 17, 2026
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0 309 August 13, 2026
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1 362 August 5, 2026
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Questions
3 895 August 10, 2026
BSSE error input file
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5 924 August 10, 2026
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0 375 August 5, 2026
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Announcements
0 379 July 28, 2026
CDFT-CI convergence issue
Questions
1 417 July 26, 2026
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1 433 July 24, 2026
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1 1075 March 12, 2023
Some doubt regarding CAP onset
Questions
3 458 July 6, 2026
Calculation of transition density matrices between CVS-ADC(2)-x excited states
Questions
0 383 June 30, 2026